Scheduling request and consistent LBT failure recovery

ABSTRACT

A wireless device receives first configuration parameters of a SR configuration associated with recovery from an LBT event comprising a plurality of LBT failures. The wireless device may trigger the LBT event for first cell(s). In response to no uplink resources, on second cell(s) for which the LBT event is not triggered, being available for transmission of an LBT failure control element, the wireless device may transmit a SR via a SR resource based on the first configuration parameters. At least one of the SR resource and the SR configuration may indicate a serving cell. The wireless device may transmit the LBT failure control element based on an uplink grant for the serving cell.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.17/105,597, filed Nov. 26, 2020, which claims the benefit of claims thebenefit of U.S. Provisional Application No. 62/942,188, filed Dec. 1,2019, which is hereby incorporated by reference in its entirety.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A and FIG. 1B show examples of mobile communications systems inaccordance with several of various embodiments of the presentdisclosure.

FIG. 2A and FIG. 2B show examples of user plane and control planeprotocol layers in accordance with several of various embodiments of thepresent disclosure.

FIG. 3 shows example functions and services offered by protocol layersin a user plane protocol stack in accordance with several of variousembodiments of the present disclosure.

FIG. 4 shows example flow of packets through the protocol layers inaccordance with several of various embodiments of the presentdisclosure.

FIG. 5A shows example mapping of channels between layers of the protocolstack and different physical signals in downlink in accordance withseveral of various embodiments of the present disclosure.

FIG. 5B shows example mapping of channels between layers of the protocolstack and different physical signals in uplink in accordance withseveral of various embodiments of the present disclosure.

FIG. 6 shows example physical layer processes for signal transmission inaccordance with several of various embodiments of the presentdisclosure.

FIG. 7 shows examples of RRC states and RRC state transitions inaccordance with several of various embodiments of the presentdisclosure.

FIG. 8 shows an example time domain transmission structure in NR bygrouping OFDM symbols into slots, subframes and frames in accordancewith several of various embodiments of the present disclosure.

FIG. 9 shows an example of time-frequency resource grid in accordancewith several of various embodiments of the present disclosure.

FIG. 10 shows example adaptation and switching of bandwidth parts inaccordance with several of various embodiments of the presentdisclosure.

FIG. 11A shows example arrangements of carriers in carrier aggregationin accordance with several of various embodiments of the presentdisclosure.

FIG. 11B shows examples of uplink control channel groups in accordancewith several of various embodiments of the present disclosure.

FIG. 12A, FIG. 12B and FIG. 12C show example random access processes inaccordance with several of various embodiments of the presentdisclosure.

FIG. 13A shows example time and frequency structure of SSBs and theirassociations with beams in accordance with several of variousembodiments of the present disclosure.

FIG. 13B shows example time and frequency structure of CSI-RSs and theirassociation with beams in accordance with several of various embodimentsof the present disclosure.

FIG. 14A, FIG. 14B and FIG. 14C show example beam management processesin accordance with several of various embodiments of the presentdisclosure.

FIG. 15 shows example components of a wireless device and a base stationthat are in communication via an air interface in accordance withseveral of various embodiments of the present disclosure.

FIG. 16 shows example channel access parameters for listen before talkin accordance with several of various embodiments of the presentdisclosure.

FIG. 17A, FIG. 17B and FIG. 17C show example MAC sub-headers inaccordance with several of various embodiments of the presentdisclosure.

FIG. 18 shows an example MAC protocol data unit (MAC PDU) in accordancewith several of various embodiments of the present disclosure.

FIG. 19 shows an example process in accordance with several of variousembodiments of the present disclosure.

FIG. 20 shows an example process in accordance with several of variousembodiments of the present disclosure.

FIG. 21 shows example LBT failure indication MAC CE formats inaccordance with several of various embodiments of the presentdisclosure.

FIG. 22 shows example LBT failure indication MAC CE formats inaccordance with several of various embodiments of the presentdisclosure.

FIG. 23 shows example scheduling request transmission for recovery fromconsistent LBT failures on one or more cells.

FIG. 24 shows an example process in accordance with several of variousembodiments of the present disclosure.

FIG. 25 shows an example process in accordance with several of variousembodiments of the present disclosure.

FIG. 26 shows an example process in accordance with several of variousembodiments of the present disclosure.

FIG. 27 shows an example process in accordance with several of variousembodiments of the present disclosure.

FIG. 28 shows an example process in accordance with several of variousembodiments of the present disclosure.

FIG. 29 shows an example process in accordance with several of variousembodiments of the present disclosure.

FIG. 30 shows an example process in accordance with several of variousembodiments of the present disclosure.

FIG. 31 shows an example process in accordance with several of variousembodiments of the present disclosure.

FIG. 32 shows an example process in accordance with several of variousembodiments of the present disclosure.

FIG. 33 shows an example consistent listen-before-talk (LBT) failurerecovery process in accordance with several of various embodiments ofthe present disclosure.

FIG. 34 shows an example consistent listen-before-talk (LBT) failurerecovery process in accordance with several of various embodiments ofthe present disclosure.

FIG. 35 shows an example consistent listen-before-talk (LBT) failurerecovery process in accordance with several of various embodiments ofthe present disclosure.

FIG. 36 shows an example consistent listen-before-talk (LBT) failurerecovery process in accordance with several of various embodiments ofthe present disclosure.

FIG. 37 shows an example consistent listen-before-talk (LBT) failurerecovery process in accordance with several of various embodiments ofthe present disclosure.

FIG. 38 shows an example flow diagram in accordance with several ofvarious embodiments of the present disclosure.

FIG. 39 shows an example flow diagram in accordance with several ofvarious embodiments of the present disclosure.

FIG. 40 shows an example flow diagram in accordance with several ofvarious embodiments of the present disclosure.

FIG. 41 shows an example flow diagram in accordance with several ofvarious embodiments of the present disclosure.

FIG. 42 shows an example flow diagram in accordance with several ofvarious embodiments of the present disclosure.

FIG. 43 shows an example flow diagram in accordance with several ofvarious embodiments of the present disclosure.

FIG. 44 shows an example flow diagram in accordance with several ofvarious embodiments of the present disclosure.

FIG. 45 shows an example flow diagram in accordance with several ofvarious embodiments of the present disclosure.

DETAILED DESCRIPTION

The exemplary embodiments of the disclosed technology enable operationof a wireless device and/or one or more base stations in unlicensed orshared spectrum. The exemplary disclosed embodiments may be implementedin the technical field of wireless communication systems. Moreparticularly, the embodiment of the disclosed technology may relate torecovery from consistent uplink listen-before-talk (LBT) failure.

The devices and/or nodes of the mobile communications system disclosedherein may be implemented based on various technologies and/or variousreleases/versions/amendments of a technology. The various technologiesinclude various releases of long-term evolution (LTE) technologies,various releases of 5G new radio (NR) technologies, various wirelesslocal area networks technologies and/or a combination thereof and/oralike. For example, a base station may support a given technology andmay communicate with wireless devices with different characteristics.The wireless devices may have different categories that define theircapabilities in terms of supporting various features. The wirelessdevice with the same category may have different capabilities. Thewireless devices may support various technologies such as variousreleases of LTE technologies, various releases of 5G NR technologiesand/or a combination thereof and/or alike. At least some of the wirelessdevices in the mobile communications system of the present disclosuremay be stationary or almost stationary. In this disclosure, the terms“mobile communications system” and “wireless communications system” maybe used interchangeably.

FIG. 1A shows an example of a mobile communications system 100 inaccordance with several of various embodiments of the presentdisclosure. The mobile communications system 100 may be, for example,run by a mobile network operator (MNO) or a mobile virtual networkoperator (MVNO). The mobile communications system 100 may be a publicland mobile network (PLMN) run by a network operator providing a varietyof service including voice, data, short messaging service (SMS),multimedia messaging service (MMS), emergency calls, etc. The mobilecommunications system 100 includes a core network (CN) 106, a radioaccess network (RAN) 104 and at least one wireless device 102.

The CN 106 connects the RAN 104 to one or more external networks (e.g.,one or more data networks such as the Internet) and is responsible forfunctions such as authentication, charging and end-to-end connectionestablishment. Several radio access technologies (RATs) may be served bythe same CN 106.

The RAN 104 may implement a RAT and may operate between the at least onewireless device 102 and the CN 106. The RAN 104 may handle radio relatedfunctionalities such as scheduling, radio resource control, modulationand coding, multi-antenna transmissions and retransmission protocols.The wireless device and the RAN may share a portion of the radiospectrum by separating transmissions from the wireless device to the RANand the transmissions from the RAN to the wireless device. The directionof the transmissions from the wireless device to the RAN is known as theuplink and the direction of the transmissions from the RAN to thewireless device is known as the downlink. The separation of uplink anddownlink transmissions may be achieved by employing a duplexingtechnique. Example duplexing techniques include frequency divisionduplexing (FDD), time division duplexing (TDD) or a combination of FDDand TDD.

In this disclosure, the term wireless device may refer to a device thatcommunicates with a network entity or another device using wirelesscommunication techniques. The wireless device may be a mobile device ora non-mobile (e.g., fixed) device. Examples of the wireless deviceinclude cellular phone, smart phone, tablet, laptop computer, wearabledevice (e.g., smart watch, smart shoe, fitness trackers, smart clothing,etc.), wireless sensor, wireless meter, extended reality (XR) devicesincluding augmented reality (AR) and virtual reality (VR) devices,Internet of Things (IoT) device, vehicle to vehicle communicationsdevice, road-side units (RSU), automobile, relay node or any combinationthereof. In some examples, the wireless device (e.g., a smart phone,tablet, etc.) may have an interface (e.g., a graphical user interface(GUI)) for configuration by an end user. In some examples, the wirelessdevice (e.g., a wireless sensor device, etc.) may not have an interfacefor configuration by an end user. The wireless device may be referred toas a user equipment (UE), a mobile station (MS), a subscriber unit, ahandset, an access terminal, a user terminal, a wireless transmit andreceive unit (WTRU) and/or other terminology.

The at least one wireless device may communicate with at least one basestation in the RAN 104. In this disclosure, the term base station mayencompass terminologies associated with various RATs. For example, abase station may be referred to as a Node B in a 3G cellular system suchas Universal Mobile Telecommunication Systems (UMTS), an evolved Node B(eNB) in a 4G cellular system such as evolved universal terrestrialradio access (E-UTRA), a next generation eNB (ng-eNB), a Next GenerationNode B (gNB) in NR and/or a 5G system, an access point (AP) in Wi-Fiand/or other wireless local area networks. A base station may bereferred to as a remote radio head (RRH), a baseband unit (BBU) inconnection with one or more RRHs, a repeater or relay for coverageextension and/or any combination thereof. In some examples, all protocollayers of a base station may be implemented in one unit. In someexample, some of the protocol layers (e.g., upper layers) of the basestation may be implemented in a first unit (e.g., a central unit (CU))and some other protocol layer (e.g., lower layers) may be implemented inone or more second units (e.g., distributed units (DUs)).

A base station in the RAN 104 includes one or more antennas tocommunicate with the at least one wireless device. The base station maycommunicate with the at least one wireless device using radio frequency(RF) transmissions and receptions via RF transceivers. The base stationantennas may control one or more cells (or sectors). The size and/orradio coverage area of a cell may depend on the range that transmissionsby a wireless device can be successfully received by the base stationwhen the wireless device transmits using the RF frequency of the cell.The base station may be associated with cells of various sizes. At agiven location, the wireless device may be in coverage area of a firstcell of the base station and may not be in coverage area of a secondcell of the base station depending on the sizes of the first cell andthe second cell.

A base station in the RAN 104 may have various implementations. Forexample, a base station may be implemented by connecting a BBU (or a BBUpool) coupled to one or more RRHs and/or one or more relay nodes toextend the cell coverage. The BBU pool may be located at a centralizedsite like a cloud or data center. The BBU pool may be connected to aplurality of RRHs that control a plurality of cells. The combination ofBBU with the one or more RRHs may be referred to as a centralized orcloud RAN (C-RAN) architecture. In some implementations, the BBUfunctions may be implemented on virtual machines (VMs) on servers at acentralized location. This architecture may be referred to as virtualRAN (vRAN). All, most or a portion of the protocol layer functions(e.g., all or portions of physical layer, medium access control (MAC)layer and/or higher layers) may be implemented at the BBU pool and theprocessed data may be transmitted to the RRHs for further processingand/or RF transmission. The links between the BBU pool and the RRHs maybe referred to as fronthaul.

In some deployment scenarios, the RAN 104 may include macrocell basestations with high transmission power levels and large coverage areas.In other deployment scenarios, the RAN 104 may include base stationsthat employ different transmission power levels and/or have cells withdifferent coverage areas. For example, some base station may bemacrocell base stations with high transmission powers and/or largecoverage areas and other base station may be small cell base stationswith comparatively smaller transmission powers and/or coverage areas. Insome deployment scenarios, a small cell base station may have coveragethat is within or has overlap with coverage area of a macrocell basestation. A wireless device may communicate with the macrocell basestation while within the coverage area of the macrocell base station.For additional capacity, the wireless device may communicate with boththe macrocell base station and the small cell base station while in theoverlapped coverage area of the macrocell base station and the smallcell base station. Depending on their coverage areas, a small cell basestation may be referred to as a microcell base station, a picocell basestation, a femtocell base station or a home base station.

Different standard development organizations (SDOs) have specified, ormay specify in future, mobile communications systems that have similarcharacteristics as the mobile communications system 100 of FIG. 1A. Forexample, the Third-Generation Partnership Project (3GPP) is a group ofSDOs that provides specifications that define 3GPP technologies formobile communications systems that are akin to the mobile communicationssystem 100. The 3GPP has developed specifications for third generation(3G) mobile networks, fourth generation (4G) mobile networks and fifthgeneration (5G) mobile networks. The 3G, 4G and 5G networks are alsoknown as Universal Mobile Telecommunications System (UMTS), Long TermEvolution (LTE) and 5G system (5GS), respectively. In this disclosure,embodiments are described with respect to the RAN implemented in a 3GPP5G mobile network that is also referred to as next generation RAN(NG-RAN). The embodiments may also be implemented in other mobilecommunications systems such as 3G or 4G mobile networks or mobilenetworks that may be standardized in future such as sixth generation(6G) mobile networks or mobile networks that are implemented bystandards bodies other than 3GPP. The NG-RAN may be based on a new RATknown as new radio (NR) and/or other radio access technologies such asLTE and/or non-3GPP RATs.

FIG. 1B shows an example of a mobile communications system 110 inaccordance with several of various embodiments of the presentdisclosure. The mobile communications system 110 of FIG. 1B is anexample of a 5G mobile network and includes a 5G CN (5G-CN) 130, anNG-RAN 120 and UEs (collectively 112 and individually UE 112A and UE112B). The 5G-CN 130, the NG-RAN 120 and the UEs 112 of FIG. 1B operatesubstantially alike the CN 106, the RAN 104 and the at least onewireless device 102, respectively, as described for FIG. 1A.

The 5G-CN 130 of FIG. 1B connects the NG-RAN 120 to one or more externalnetworks (e.g., one or more data networks such as the Internet) and isresponsible for functions such as authentication, charging andend-to-end connection establishment. The 5G-CN has new enhancementscompared to previous generations of CNs (e.g., evolved packet core (EPC)in the 4G networks) including service-based architecture, support fornetwork slicing and control plane/user plane split. The service-basedarchitecture of the 5G-CN provides a modular framework based on serviceand functionalities provided by the core network wherein a set ofnetwork functions are connected via service-based interfaces. Thenetwork slicing enables multiplexing of independent logical networks(e.g., network slices) on the same physical network infrastructure. Forexample, a network slice may be for mobile broadband applications withfull mobility support and a different network slice may be fornon-mobile latency-critical applications such as industry automation.The control plane/user plane split enables independent scaling of thecontrol plane and the user plane. For example, the control planecapacity may be increased without affecting the user plane of thenetwork.

The 5G-CN 130 of FIG. 1B includes an access and mobility managementfunction (AMF) 132 and a user plane function (UPF) 134. The AMF 132 maysupport termination of non-access stratum (NAS) signaling, NAS signalingsecurity such as ciphering and integrity protection, inter-3GPP accessnetwork mobility, registration management, connection management,mobility management, access authentication and authorization andsecurity context management. The NAS is a functional layer between a UEand the CN and the access stratum (AS) is a functional layer between theUE and the RAN. The UPF 134 may serve as an interconnect point betweenthe NG-RAN and an external data network. The UPF may support packetrouting and forwarding, packet inspection and Quality of Service (QoS)handling and packet filtering. The UPF may further act as a ProtocolData Unit (PDU) session anchor point for mobility within and betweenRATs.

The 5G-CN 130 may include additional network functions (not shown inFIG. 1B) such as one or more Session Management Functions (SMFs), aPolicy Control Function (PCF), a Network Exposure Function (NEF), aUnified Data Management (UDM), an Application Function (AF), and/or anAuthentication Server Function (AUSF). These network functions alongwith the AMF 132 and UPF 134 enable a service-based architecture for the5G-CN.

The NG-RAN 120 may operate between the UEs 112 and the 5G-CN 130 and mayimplement one or more RATs. The NG-RAN 120 may include one or more gNBs(e.g., gNB 122A or gNB 122B or collectively gNBs 122) and/or one or moreng-eNBs (e.g., ng-eNB 124A or ng-eNB 124B or collectively ng-eNB s 124).The general terminology for gNBs 122 and/or an ng-eNBs 124 is a basestation and may be used interchangeably in this disclosure. The gNBs 122and the ng-eNBs 124 may include one or more antennas to communicate withthe UEs 112. The one or more antennas of the gNBs 122 or ng-eNBs 124 maycontrol one or more cells (or sectors) that provide radio coverage forthe UEs 112.

A gNB and/or an ng-eNB of FIG. 1B may be connected to the 5G-CN 130using an NG interface. A gNB and/or an ng-eNB may be connected withother gNBs and/or ng-eNBs using an Xn interface. The NG or the Xninterfaces are logical connections that may be established using anunderlying transport network. The interface between a UE and a gNB orbetween a UE and an ng-eNBs may be referred to as the Uu interface. Aninterface (e.g., Uu, NG or Xn) may be established by using a protocolstack that enables data and control signaling exchange between entitiesin the mobile communications system of FIG. 1B. When a protocol stack isused for transmission of user data, the protocol stack may be referredto as user plane protocol stack. When a protocol stack is used fortransmission of control signaling, the protocol stack may be referred toas control plane protocol stack. Some protocol layer may be used in bothof the user plane protocol stack and the control plane protocol stackwhile other protocol layers may be specific to the user plane or controlplane.

The NG interface of FIG. 1B may include an NG-User plane (NG-U)interface between a gNB and the UPF 134 (or an ng-eNB and the UPF 134)and an NG-Control plane (NG-C) interface between a gNB and the AMF 132(or an ng-eNB and the AMF 132). The NG-U interface may providenon-guaranteed delivery of user plane PDUs between a gNB and the UPF oran ng-eNB and the UPF. The NG-C interface may provide services such asNG interface management, UE context management, UE mobility management,transport of NAS messages, paging, PDU session management, configurationtransfer and/or warning message transmission.

The UEs 112 and a gNB may be connected using the Uu interface and usingthe NR user plane and control plane protocol stack. The UEs 112 and anng-eNB may be connected using the Uu interface using the LTE user planeand control plane protocol stack.

In the example mobile communications system of FIG. 1B, a 5G-CN isconnected to a RAN comprised of 4G LTE and/or 5G NR RATs. In otherexample mobile communications systems, a RAN based on the 5G NR RAT maybe connected to a 4G CN (e.g., EPC). For example, earlier releases of 5Gstandards may support a non-standalone mode of operation where a NRbased RAN is connected to the 4G EPC. In an example non-standalone mode,a UE may be connected to both a 5G NR gNB and a 4G LTE eNB (e.g., ang-eNB) and the control plane functionalities (such as initial access,paging and mobility) may be provided through the 4G LTE eNB. In astandalone of operation, the 5G NR gNB is connected to a 5G-CN and theuser plane and the control plane functionalities are provided by the 5GNR gNB.

FIG. 2A shows an example of the protocol stack for the user plan of anNR Uu interface in accordance with several of various embodiments of thepresent disclosure. The user plane protocol stack comprises fiveprotocol layers that terminate at the UE 200 and the gNB 210. The fiveprotocol layers, as shown in FIG. 2A, include physical (PHY) layerreferred to as PHY 201 at the UE 200 and PHY 211 at the gNB 210, mediumaccess control (MAC) layer referred to as MAC 202 at the UE 200 and MAC212 at the gNB 210, radio link control (RLC) layer referred to as RLC203 at the UE 200 and RLC 213 at the gNB 210, packet data convergenceprotocol (PDCP) layer referred to as PDCP 204 at the UE 200 and PDCP 214at the gNB 210, and service data application protocol (SDAP) layerreferred to as SDAP 205 at the UE 200 and SDAP 215 at the gNB 210. ThePHY layer, also known as layer 1 (L1), offers transport services tohigher layers. The other four layers of the protocol stack (MAC, RLC,PDCP and SDAP) are collectively known as layer 2 (L2).

FIG. 2B shows an example of the protocol stack for the control plan ofan NR Uu interface in accordance with several of various embodiments ofthe present disclosure. Some of the protocol layers (PHY, MAC, RLC andPDCP) are common between the user plane protocol stack shown in FIG. 2Aand the control plan protocol stack. The control plane protocol stackalso includes the RRC layer, referred to RRC 206 at the UE 200 and RRC216 at the gNB 210, that also terminates at the UE 200 and the gNB 210.In addition, the control plane protocol stack includes the NAS layerthat terminates at the UE 200 and the AMF 220. In FIG. 2B, the NAS layeris referred to as NAS 207 at the UE 200 and NAS 227 at the AMF 220.

FIG. 3 shows example functions and services offered to other layers by alayer in the NR user plane protocol stack of FIG. 2A in accordance withseveral of various embodiments of the present disclosure. For example,the SDAP layer of FIG. 3 (shown in FIG. 2A as SDAP 205 at the UE sideand SDAP 215 at the gNB side) may perform mapping and de-mapping of QoSflows to data radio bearers. The mapping and de-mapping may be based onQoS (e.g., delay, throughput, jitter, error rate, etc.) associated witha QoS flow. A QoS flow may be a QoS differentiation granularity for aPDU session which is a logical connection between a UE 200 and a datanetwork. A PDU session may contain one or more QoS flows. The functionsand services of the SDAP layer include mapping and de-mapping betweenone or more QoS flows and one or more data radio bearers. The SDAP layermay also mark the uplink and/or downlink packets with a QoS flow ID(QFI).

The PDCP layer of FIG. 3 (shown in FIG. 2A as PDCP 204 at the UE sideand PDCP 214 at the gNB side) may perform header compression anddecompression (e.g., using Robust Header Compression (ROHC) protocol) toreduce the protocol header overhead, ciphering and deciphering andintegrity protection and verification to enhance the security over theair interface, reordering and in-order delivery of packets anddiscarding of duplicate packets. A UE may be configured with one PDCPentity per bearer.

In an example scenario not shown in FIG. 3, a UE may be configured withdual connectivity and may connect to two different cell groups providedby two different base stations. For example, a base station of the twobase stations may be referred to as a master base station and a cellgroup provided by the master base station may be referred to as a mastercell group (MCG). The other base station of the two base stations may bereferred to as a secondary base station and the cell group provided bythe secondary base station may be referred to as a secondary cell group(SCG). A bearer may be configured for the UE as a split bearer that maybe handled by the two different cell groups. The PDCP layer may performrouting of packets corresponding to a split bearer to and/or from RLCchannels associated with the cell groups.

In an example scenario not shown in FIG. 3, a bearer of the UE may beconfigured (e.g., with control signaling) with PDCP packet duplication.A bearer configured with PDCP duplication may be mapped to a pluralityof RLC channels each corresponding to different one or more cells. ThePDCP layer may duplicate packets of the bearer configured with PDCPduplication and the duplicated packets may be mapped to the differentRLC channels. With PDCP packet duplication, the likelihood of correctreception of packets increases thereby enabling higher reliability.

The RLC layer of FIG. 3 (shown in FIG. 2A as RLC 203 at the UE side andRLC 213 at the gNB side) provides service to upper layers in the form ofRLC channels. The RLC layer may include three transmission modes:transparent mode (TM), Unacknowledged mode (UM) and Acknowledged mode(AM). The RLC layer may perform error correction through automaticrepeat request (ARQ) for the AM transmission mode, segmentation of RLCservice data units (SDUs) for the AM and UM transmission modes andre-segmentation of RLC SDUs for AM transmission mode, duplicatedetection for the AM transmission mode, RLC SDU discard for the AM andUM transmission modes, etc. The UE may be configured with one RLC entityper RLC channel.

The MAC layer of FIG. 3 (shown in FIG. 2A as MAC 202 at the UE side andMAC 212 at the gNB side) provides services to the RLC layer in form oflogical channels. The MAC layer may perform mapping between logicalchannels and transport channels, multiplexing/demultiplexing of MAC SDUsbelonging to one or more logical channels into/from transport blocks(TBs) delivered to/from the physical layer on transport channels,reporting of scheduling information, error correction through hybridautomatic repeat request (HARM), priority handling between UEs by meansof dynamic scheduling, priority handling between logical channels of oneUE by means of logical channel prioritization and/or padding. In case ofcarrier aggregation, a MAC entity may comprise one HARQ entity per cell.A MAC entity may support multiple numerologies, transmission timings andcells. The control signaling may configure logical channels with mappingrestrictions. The mapping restrictions in logical channel prioritizationmay control the numerology(ies), cell(s), and/or transmissiontiming(s)/duration(s) that a logical channel may use.

The PHY layer of FIG. 3 (shown in FIG. 2A as PHY 201 at the UE side andPHY 211 at the gNB side) provides transport services to the MAC layer inform of transport channels. The physical layer may handlecoding/decoding, HARQ soft combining, rate matching of a coded transportchannel to physical channels, mapping of coded transport channels tophysical channels, modulation and demodulation of physical channels,frequency and time synchronization, radio characteristics measurementsand indication to higher layers, RF processing, and mapping to antennasand radio resources.

FIG. 4 shows example processing of packets at different protocol layersin accordance with several of various embodiments of the presentdisclosure. In this example, three Internet Protocol (IP) packets thatare processed by the different layers of the NR protocol stack. The termSDU shown in FIG. 4 is the data unit that is entered from/to a higherlayer. In contrast, a protocol data unit (PDU) is the data unit that isentered to/from a lower layer. The flow of packets in FIG. 4 is fordownlink. An uplink data flow through layers of the NR protocol stack issimilar to FIG. 4. In this example, the two leftmost IP packets aremapped by the SDAP layer (shown as SDAP 205 and SDAP 215 in FIG. 2A) toradio bearer 402 and the rightmost packet is mapped by the SDAP layer tothe radio bearer 404. The SDAP layer adds SDAP headers to the IP packetswhich are entered into the PDCP layer as PDCP SDUs. The PDCP layer isshown as PDCP 204 and PDCP 214 in FIG. 2A. The PDCP layer adds the PDCPheaders to the PDCP SDUs which are entered into the RLC layer as RLCSDUs. The RLC layer is shown as RLC 203 and RLC 213 in FIG. 2A. An RLCSDU may be segmented at the RLC layer. The RLC layer adds RLC headers tothe RLC SDUs after segmentation (if segmented) which are entered intothe MAC layer as MAC SDUs. The MAC layer adds the MAC headers to the MACSDUs and multiplexes one or more MAC SDUs to form a PHY SDU (alsoreferred to as a transport block (TB) or a MAC PDU).

In FIG. 4, the MAC SDUs are multiplexed to form a transport block. TheMAC layer may multiplex one or more MAC control elements (MAC CEs) withzero or more MAC SDUs to form a transport block. The MAC CEs may also bereferred to as MAC commands or MAC layer control signaling and may beused for in-band control signaling. The MAC CEs may be transmitted by abase station to a UE (e.g., downlink MAC CEs) or by a UE to a basestation (e.g., uplink MAC CEs). The MAC CEs may be used for transmissionof information useful by a gNB for scheduling (e.g., buffer statusreport (BSR) or power headroom report (PHR)), activation/deactivation ofone or more cells, activation/deactivation of configured radio resourcesfor or one or more processes, activation/deactivation of one or moreprocesses, indication of parameters used in one or more processes, etc.

FIG. 5A and FIG. 5B show example mapping between logical channels,transport channels and physical channels for downlink and uplink,respectively in accordance with several of various embodiments of thepresent disclosure. As discussed before, the MAC layer provides servicesto higher layer in the form of logical channels. A logical channel maybe classified as a control channel, if used for transmission of controland/or configuration information, or a traffic channel if used fortransmission of user data. Example logical channels in NR includeBroadcast Control Channel (BCCH) used for transmission of broadcastsystem control information, Paging Control Channel (PCCH) used forcarrying paging messages for wireless devices with unknown locations,Common Control Channel (CCCH) used for transmission of controlinformation between UEs and network and for UEs that have no RRCconnection with the network, Dedicated Control Channel (DCCH) which is apoint-to-point bi-directional channel for transmission of dedicatedcontrol information between a UE that has an RRC connection and thenetwork and Dedicated Traffic Channel (DTCH) which is point-to-pointchannel, dedicated to one UE, for the transfer of user information andmay exist in both uplink and downlink.

As discussed before, the PHY layer provides services to the MAC layerand higher layers in the form of transport channels. Example transportchannels in NR include Broadcast Channel (BCH) used for transmission ofpart of the BCCH referred to as master information block (MIB), DownlinkShared Channel (DL-SCH) used for transmission of data (e.g., from DTCHin downlink) and various control information (e.g., from DCCH and CCCHin downlink and part of the BCCH that is not mapped to the BCH), UplinkShared Channel (UL-SCH) used for transmission of uplink data (e.g., fromDTCH in uplink) and control information (e.g., from CCCH and DCCH inuplink) and Paging Channel (PCH) used for transmission of paginginformation from the PCCH. In addition, Random Access Channel (RACH) isa transport channel used for transmission of random access preambles.The RACH does not carry a transport block. Data on a transport channel(except RACH) may be organized in transport blocks, wherein One or moretransport blocks may be transmitted in a transmission time interval(TTI).

The PHY layer may map the transport channels to physical channels. Aphysical channel may correspond to time-frequency resources that areused for transmission of information from one or more transportchannels. In addition to mapping transport channels to physicalchannels, the physical layer may generate control information (e.g.,downlink control information (DCI) or uplink control information (UCI))that may be carried by the physical channels. Example DCI includescheduling information (e.g., downlink assignments and uplink grants),request for channel state information report, power control command,etc. Example UCI include HARQ feedback indicating correct or incorrectreception of downlink transport blocks, channel state informationreport, scheduling request, etc. Example physical channels in NR includea Physical Broadcast Channel (PBCH) for carrying information from theBCH, a Physical Downlink Shared Channel (PDSCH) for carrying informationform the PCH and the DL-SCH, a Physical Downlink Control Channel (PDCCH)for carrying DCI, a Physical Uplink Shared Channel (PUSCH) for carryinginformation from the UL-SCH and/or UCI, a Physical Uplink ControlChannel (PUCCH) for carrying UCI and Physical Random Access Channel(PRACH) for transmission of RACH (e.g., random access preamble).

The PHY layer may also generate physical signals that are not originatedfrom higher layers. As shown in FIG. 5A, example downlink physicalsignals include Demodulation Reference Signal (DM-RS), Phase TrackingReference Signal (PT-RS), Channel State Information Reference Signal(CSI-RS), Primary Synchronization Signal (PSS) and SecondarySynchronization Signal (SSS). As shown in FIG. 5B, example uplinkphysical signals include DM-RS, PT-RS and sounding reference signal(SRS).

As indicated earlier, some of the protocol layers (PHY, MAC, RLC andPDCP) of the control plane of an NR Uu interface, are common between theuser plane protocol stack (as shown in FIG. 2A) and the control planeprotocol stack (as shown in FIG. 2B). In addition to PHY, MAC, RLC andPDCP, the control plane protocol stack includes the RRC protocol layerand the NAS protocol layer.

The NAS layer, as shown in FIG. 2B, terminates at the UE 200 and the AMF220 entity of the 5G-C 130. The NAS layer is used for core networkrelated functions and signaling including registration, authentication,location update and session management. The NAS layer uses services fromthe AS of the Uu interface to transmit the NAS messages.

The RRC layer, as shown in FIG. 2B, operates between the UE 200 and thegNB 210 (more generally NG-RAN 120) and may provide services andfunctions such as broadcast of system information (SI) related to AS andNAS as well as paging initiated by the 5G-C 130 or NG-RAN 120. Inaddition, the RRC layer is responsible for establishment, maintenanceand release of an RRC connection between the UE 200 and the NG-RAN 120,carrier aggregation configuration (e.g., addition, modification andrelease), dual connectivity configuration (e.g., addition, modificationand release), security related functions, radio bearerconfiguration/maintenance and release, mobility management (e.g.,maintenance and context transfer), UE cell selection and reselection,inter-RAT mobility, QoS management functions, UE measurement reportingand control, radio link failure (RLF) detection and NAS messagetransfer. The RRC layer uses services from PHY, MAC, RLC and PDCP layersto transmit RRC messages using signaling radio bearers (SRBs). The SRBsare mapped to CCCH logical channel during connection establishment andto DCCH logical channel after connection establishment.

FIG. 6 shows example physical layer processes for signal transmission inaccordance with several of various embodiments of the presentdisclosure. Data and/or control streams from MAC layer may beencoded/decoded to offer transport and control services over the radiotransmission link. For example, one or more (e.g., two as shown in FIG.6) transport blocks may be received from the MAC layer for transmissionvia a physical channel (e.g., a physical downlink shared channel or aphysical uplink shared channel). A cyclic redundancy check (CRC) may becalculated and attached to a transport block in the physical layer. TheCRC calculation may be based on one or more cyclic generatorpolynomials. The CRC may be used by the receiver for error detection.Following the transport block CRC attachment, a low-density parity check(LDPC) base graph selection may be performed. In example embodiments,two LDPC base graphs may be used wherein a first LDPC base graph may beoptimized for small transport blocks and a second LDPC base graph may beoptimized for comparatively larger transport blocks.

The transport block may be segmented into code blocks and code block CRCmay be calculated and attached to a code block. A code block may be LDPCcoded and the LDPC coded blocks may be individually rate matched. Thecode blocks may be concatenated to create one or more codewords. Thecontents of a codeword may be scrambled and modulated to generate ablock of complex-valued modulation symbols. The modulation symbols maybe mapped to a plurality of transmission layers (e.g., multiple-inputmultiple-output (MIMO) layers) and the transmission layers may besubject to transform precoding and/or precoding. The precodedcomplex-valued symbols may be mapped to radio resources (e.g., resourceelements). The signal generator block may create a baseband signal andup-convert the baseband signal to a carrier frequency for transmissionvia antenna ports. The signal generator block may employ mixers, filtersand/or other radio frequency (RF) components prior to transmission viathe antennas. The functions and blocks in FIG. 6 are illustrated asexamples and other mechanisms may be implemented in various embodiments.

FIG. 7 shows examples of RRC states and RRC state transitions at a UE inaccordance with several of various embodiments of the presentdisclosure. A UE may be in one of three RRC states: RRC_IDLE 702,RRC_INACTIVE 704 and RRC_CONNECTED 706. In RRC_IDLE 702 state, no RRCcontext (e.g., parameters needed for communications between the UE andthe network) may be established for the UE in the RAN. In RRC_IDLE 702state, no data transfer between the UE and the network may take placeand uplink synchronization is not maintained. The wireless device maysleep most of the time and may wake up periodically to receive pagingmessages. The uplink transmission of the UE may be based on a randomaccess process and to enable transition to the RRC_CONNECTED 706 state.The mobility in RRC_IDLE 702 state is through a cell reselectionprocedure where the UE camps on a cell based on one or more criteriaincluding signal strength that is determined based on the UEmeasurements.

In RRC_CONNECTED 706 state, the RRC context is established and both theUE and the RAN have necessary parameters to enable communicationsbetween the UE and the network. In the RRC_CONNECTED 706 state, the UEis configured with an identity known as a Cell Radio Network TemporaryIdentifier (C-RNTI) that is used for signaling purposes (e.g., uplinkand downlink scheduling, etc.) between the UE and the RAN. The wirelessdevice mobility in the RRC_CONNECTED 706 state is managed by the RAN.The wireless device provides neighboring cells and/or current servingcell measurements to the network and the network may make hand overdecisions. Based on the wireless device measurements, the currentserving base station may send a handover request message to aneighboring base station and may send a handover command to the wirelessdevice to handover to a cell of the neighboring base station. Thetransition of the wireless device from the RRC_IDLE 702 state to theRRC_CONNECTED 706 state or from the RRC_CONNECTED 706 state to theRRC_IDLE 702 state may be based on connection establishment andconnection release procedures (shown collectively as connectionestablishment/release 710 in FIG. 7).

To enable a faster transition to the RRC_CONNECTED 706 state (e.g.,compared to transition from RRC_IDLE 702 state to RRC_CONNECTED 706state), an RRC_INACTIVE 704 state is used for an NR UE wherein, the RRCcontext is kept at the UE and the RAN. The transition from theRRC_INACTIVE 704 state to the RRC_CONNECTED 706 state is handled by RANwithout CN signaling. Similar to the RRC_IDLE 702 state, the mobility inRRC_INACTIVE 704 state is based on a cell reselection procedure withoutinvolvement from the network. The transition of the wireless device fromthe RRC_INACTIVE 704 state to the RRC_CONNECTED 706 state or from theRRC_CONNECTED 706 state to the RRC_INACTIVE 704 state may be based onconnection resume and connection inactivation procedures (showncollectively as connection resume/inactivation 712 in FIG. 7). Thetransition of the wireless device from the RRC_INACTIVE 704 state to theRRC_IDLE 702 state may be based on a connection release 714 procedure asshown in FIG. 7.

In NR, Orthogonal Frequency Division Multiplexing (OFDM), also calledcyclic prefix OFDM (CP-OFDM), is the baseline transmission scheme inboth downlink and uplink of NR and the Discrete Fourier Transform (DFT)spread OFDM (DFT-s-OFDM) is a complementary uplink transmission inaddition to the baseline OFDM scheme. OFDM is multi-carrier transmissionscheme wherein the transmission bandwidth may be composed of severalnarrowband sub-carriers. The subcarriers are modulated by the complexvalued OFDM modulation symbols resulting in an OFDM signal. The complexvalued OFDM modulation symbols are obtained by mapping, by a modulationmapper, the input data (e.g., binary digits) to different points of amodulation constellation diagram. The modulation constellation diagramdepends on the modulation scheme. NR may use different types ofmodulation schemes including Binary Phase Shift Keying (BPSK), π/2-BPSK,Quadrature Phase Shift Keying (QPSK), 16 Quadrature Amplitude Modulation(16QAM), 64QAM and 256QAM. Different and/or higher order modulationschemes (e.g., M-QAM in general) may be used. An OFDM signal with Nsubcarriers may be generated by processing N subcarriers in parallel forexample by using Inverse Fast Fourier Transform (IFFT) processing. TheOFDM receiver may use FFT processing to recover the transmitted OFDMmodulation symbols. The subcarrier spacing of subcarriers in an OFDMsignal is inversely proportional to an OFDM modulation symbol duration.For example, for a 15 KHz subcarrier spacing, duration of an OFDM signalis nearly 66.7 μs. To enhance the robustness of OFDM transmission intime dispersive channels, a cyclic prefix (CP) may be inserted at thebeginning of an OFDM symbol. For example, the last part of an OFDMsymbol may be copied and inserted at the beginning of an OFDM symbol.The CP insertion enhanced the OFDM transmission scheme by preservingsubcarrier orthogonality in time dispersive channels.

In NR, different numerologies may be used for OFDM transmission. Anumerology of OFDM transmission may indicate a subcarrier spacing and aCP duration for the OFDM transmission. For example, a subcarrier spacingin NR may generally be a multiple of 15 KHz and expressed as Δf=2^(μ).15 KHz (μ=0, 1, 2, . . . ). Example subcarrier spacings used in NRinclude 15 KHz (μ=0), 30 KHz (μ=1), 60 KHz (μ=2), 120 KHz (μ=3) and 240KHz (μ=4). As discussed before, a duration of OFDM symbol is inverselyproportional to the subcarrier spacing and therefor OFDM symbol durationmay depend on the numerology (e.g. the μ value).

FIG. 8 shows an example time domain transmission structure in NR whereinOFDM symbols are grouped into slots, subframes and frames in accordancewith several of various embodiments of the present disclosure. A slot isa group of N_(symb) ^(slot) OFDM symbols, wherein the N_(symb) ^(slot)may have a constant value (e.g., 14). Since different numerologiesresults in different OFDM symbol durations, duration of a slot may alsodepend on the numerology and may be variable. A subframe may have aduration of 1 ms and may be composed of one or more slots, the number ofwhich may depend on the slot duration. The number of slots per subframeis therefore a function of μ and may generally expressed as N_(slot)^(subframe,μ) and the number of symbols per subframe may be expressed asN_(symb) ^(subframe,μ)=N_(symb) ^(slot)N_(slot) ^(subframe,μ). A framemay have a duration of 10 ms and may consist of 10 subframes. The numberof slots per frame may depend on the numerology and therefore may bevariable. The number of slots per frame may generally be expressed asN_(slot) ^(frame,μ).

An antenna port may be defined as a logical entity such that channelcharacteristics over which a symbol on the antenna port is conveyed maybe inferred from the channel characteristics over which another symbolon the same antenna port is conveyed. For example, for DM-RS associatedwith a PDSCH, the channel over which a PDSCH symbol on an antenna portis conveyed may be inferred from the channel over which a DM-RS symbolon the same antenna port is conveyed, for example, if the two symbolsare within the same resource as the scheduled PDSCH and/or in the sameslot and/or in the same precoding resource block group (PRG). Forexample, for DM-RS associated with a PDCCH, the channel over which aPDCCH symbol on an antenna port is conveyed may be inferred from thechannel over which a DM-RS symbol on the same antenna port is conveyedif, for example, the two symbols are within resources for which the UEmay assume the same precoding being used. For example, for DM-RSassociated with a PBCH, the channel over which a PBCH symbol on oneantenna port is conveyed may be inferred from the channel over which aDM-RS symbol on the same antenna port is conveyed if, for example, thetwo symbols are within a SS/PBCH block transmitted within the same slot,and with the same block index. The antenna port may be different from aphysical antenna. An antenna port may be associated with an antenna portnumber and different physical channels may correspond to differentranges of antenna port numbers.

FIG. 9 shows an example of time-frequency resource grid in accordancewith several of various embodiments of the present disclosure. Thenumber of subcarriers in a carrier bandwidth may be based on thenumerology of OFDM transmissions in the carrier. A resource element,corresponding to one symbol duration and one subcarrier, may be thesmallest physical resource in the time-frequency grid. A resourceelement (RE) for antenna port p and subcarrier spacing configuration μmay be uniquely identified by (k,l)_(p,μ) where k is the index of asubcarrier in the frequency domain and l may refer to the symbolposition in the time domain relative to some reference point. A resourceblock may be defined as N_(SC) ^(RB)=12 subcarriers. Since subcarrierspacing depends on the numerology of OFDM transmission, the frequencydomain span of a resource block may be variable and may depend on thenumerology. For example, for a subcarrier spacing of 15 KHz (e.g., μ=0),a resource block may be 180 KHz and for a subcarrier spacing of 30 KHz(e.g., μ=1), a resource block may be 360 KHz.

With large carrier bandwidths defined in NR and due to limitedcapabilities for some UEs (e.g., due to hardware limitations), a UE maynot support an entire carrier bandwidth. Receiving on the full carrierbandwidth may imply high energy consumption. For example, transmittingdownlink control channels on the full downlink carrier bandwidth mayresult in high power consumption for wide carrier bandwidths. NR may usea bandwidth adaptation procedure to dynamically adapt the transmit andreceive bandwidths. The transmit and receive bandwidth of a UE on a cellmay be smaller than the bandwidth of the cell and may be adjusted. Forexample, the width of the transmit and/or receive bandwidth may change(e.g. shrink during period of low activity to save power); the locationof the transmit and/or receive bandwidth may move in the frequencydomain (e.g. to increase scheduling flexibility); and the subcarrierspacing of the transmit or receive bandwidth may change (e.g. to allowdifferent services). A subset of the cell bandwidth may be referred toas a Bandwidth Part (BWP) and bandwidth adaptation may be achieved byconfiguring the UE with one or more BWPs. The base station may configurea UE with a set of downlink BWPs and a set of uplink BWPs. A BWP may becharacterized by a numerology (e.g., subcarrier spacing and cyclicprefix) and a set of consecutive resource blocks in the numerology ofthe BWP. One or more first BWPs of the one or more BWPs of the cell maybe active at a time. An active BWP may be an active downlink BWP or anactive uplink BWP.

FIG. 10 shows an example of bandwidth part adaptation and switching. Inthis example, three BWPs (BWP₁ 1004, BWP₂ 1006 and BWP₃ 1008) areconfigured for a UE on a carrier bandwidth. The BWP₁ is configured witha bandwidth of 40 MHz and a numerology with subcarrier spacing of 15KHz, the BWP₂ is configured with a bandwidth of 10 MHz and a numerologywith subcarrier spacing of 15 KHz and the BWP₃ is configured with abandwidth of 20 MHz and a subcarrier spacing of 60 KHz. The wirelessdevice may switch from a first BWP (e.g., BWP₁) to a second BWP (e.g.,BWP₂). An active BWP of the cell may change from the first BWP to thesecond BWP in response to the BWP switching.

The BWP switching (e.g., BWP switching 1010, BWP switching 1012, BWPswitching 1014, or BWP switching 1016 in FIG. 10) may be based on acommand from the base station. The command may be a DCI comprisingscheduling information for the UE in the second BWP. In case of uplinkBWP switching, the first BWP and the second BWP may be uplink BWPs andthe scheduling information may be an uplink grant for uplinktransmission via the second BWP. In case of downlink BWP switching, thefirst BWP and the second BWP may be downlink BWPs and the schedulinginformation may be a downlink assignment for downlink reception via thesecond BWP.

The BWP switching (e.g., BWP switching 1010, BWP switching 1012, BWPswitching 1014, or BWP switching 1016 in FIG. 10) may be based on anexpiry of a timer. The base station may configure a wireless device witha BWP inactivity timer and the wireless device may switch to a defaultBWP (e.g., default downlink BWP) based on the expiry of the BWPinactivity timer. The expiry of the BWP inactivity timer may be anindication of low activity on the current active downlink BWP. The basestation may configure the wireless device with the default downlink BWP.If the base station does not configure the wireless device with thedefault BWP, the default BWP may be an initial downlink BWP. The initialactive BWP may be the BWP that the wireless device receives schedulinginformation for remaining system information upon transition to anRRC_CONNECTED state.

A wireless device may monitor a downlink control channel of a downlinkBWP. For example, the UE may monitor a set of PDCCH candidates inconfigured monitoring occasions in one or more configured COntrolREsource SETs (CORESETs) according to the corresponding search spaceconfigurations. A search space configuration may define how/where tosearch for PDCCH candidates. For example, the search space configurationparameters may comprise a monitoring periodicity and offset parameterindicating the slots for monitoring the PDCCH candidates. The searchspace configuration parameters may further comprise a parameterindicating a first symbol with a slot within the slots determined formonitoring PDCCH candidates. A search space may be associated with oneor more CORESETs and the search space configuration may indicate one ormore identifiers of the one or more CORESETs. The search spaceconfiguration parameters may further indicate that whether the searchspace is a common search space or a UE-specific search space. A commonsearch space may be monitored by a plurality of wireless devices and aUE-specific search space may be dedicated to a specific UE.

FIG. 11A shows example arrangements of carriers in carrier aggregationin accordance with several of various embodiments of the presentdisclosure. With carrier aggregation, multiple NR component carriers(CCs) may be aggregated. Downlink transmissions to a wireless device maytake place simultaneously on the aggregated downlink CCs resulting inhigher downlink data rates. Uplink transmissions from a wireless devicemay take place simultaneously on the aggregated uplink CCs resulting inhigher uplink data rates. The component carriers in carrier aggregationmay be on the same frequency band (e.g., intra-band carrier aggregation)or on different frequency bands (e.g., inter-band carrier aggregation).The component carriers may also be contiguous or non-contiguous. Thisresults in three possible carrier aggregation scenarios, intra-bandcontiguous CA 1102, intra-band non-contiguous CA 1104 and inter-band CA1106 as shown in FIG. 11A. Depending on the UE capability for carrieraggregation, a UE may transmit and/or receive on multiple carriers orfor a UE that is not capable of carrier aggregation, the UE may transmitand/or receive on one component carrier at a time. In this disclosure,the carrier aggregation is described using the term cell and a carrieraggregation capable UE may transmit and/or receive via multiple cells.

In carrier aggregation, a UE may be configured with multiple cells. Acell of the multiple cells configured for the UE may be referred to as aPrimary Cell (PCell). The PCell may be the first cell that the UE isinitially connected to. One or more other cells configured for the UEmay be referred to as Secondary Cells (SCells). The base station mayconfigure a UE with multiple SCells. The configured SCells may bedeactivated upon configuration and the base station may dynamicallyactivate or deactivate one or more of the configured SCells based ontraffic and/or channel conditions. The base station may activate ordeactivate configured SCells using a SCell Activation/Deactivation MACCE. The SCell Activation/Deactivation MAC CE may comprise a bitmap,wherein each bit in the bitmap may correspond to a SCell and the valueof the bit indicates an activation status or deactivation status of theSCell.

An SCell may also be deactivated in response to expiry of a SCelldeactivation timer of the SCell. The expiry of an SCell deactivationtimer of an SCell may be an indication of low activity (e.g., lowtransmission or reception activity) on the SCell. The base station mayconfigure the SCell with an SCell deactivation timer. The base stationmay not configure an SCell deactivation timer for an SCell that isconfigured with PUCCH (also referred to as a PUCCH SCell). Theconfiguration of the SCell deactivation timer may be per configuredSCell and different SCells may be configured with different SCelldeactivation timer values. The SCell deactivation timer may be restartedbased on one or more criteria including reception of downlink controlinformation on the SCell indicating uplink grant or downlink assignmentfor the SCell or reception of downlink control information on ascheduling cell indicating uplink grant or downlink assignment for theSCell or transmission of a MAC PDU based on a configured uplink grant orreception of a configured downlink assignment.

A PCell for a UE may be an SCell for another UE and a SCell for a UE maybe PCell for another UE. The configuration of PCell may be UE-specific.One or more SCells of the multiple SCells configured for a UE may beconfigured as downlink-only SCells, e.g., may only be used for downlinkreception and may not be used for uplink transmission. In case ofself-scheduling, the base station may transmit signaling for uplinkgrants and/or downlink assignments on the same cell that thecorresponding uplink or downlink transmission takes place. In case ofcross-carrier scheduling, the base station may transmit signaling foruplink grants and/or downlink assignments on a cell different from thecell that the corresponding uplink or downlink transmission takes place.

FIG. 11B shows examples of uplink control channel groups in accordancewith several of various embodiments of the present disclosure. A basestation may configure a UE with multiple PUCCH groups wherein a PUCCHgroup comprises one or more cells. For example, as shown in FIG. 11B,the base station may configure a UE with a primary PUCCH group 1114 anda secondary PUCCH group 1116. The primary PUCCH group may comprise thePCell 1110 and one or more first SCells. First UCI corresponding to thePCell and the one or more first SCells of the primary PUCCH group may betransmitted by the PUCCH of the PCell. The first UCI may be, forexample, HARQ feedback for downlink transmissions via downlink CCs ofthe PCell and the one or more first SCells. The secondary PUCCH groupmay comprise a PUCCH SCell and one or more second SCells. Second UCIcorresponding to the PUCCH SCell and the one or more second SCells ofthe secondary PUCCH group may be transmitted by the PUCCH of the PUCCHSCell. The second UCI may be, for example, HARQ feedback for downlinktransmissions via downlink CCs of the PUCCH SCell and the one or moresecond SCells.

FIG. 12A, FIG. 12B and FIG. 12C show example random access processes inaccordance with several of various embodiments of the presentdisclosure. FIG. 12A shows an example of four step contention-basedrandom access (CBRA) procedure. The four-step CBRA procedure includesexchanging four messages between a UE and a base station. Msg1 may befor transmission (or retransmission) of a random access preamble by thewireless device to the base station. Msg2 may be the random accessresponse (RAR) by the base station to the wireless device. Msg3 is thescheduled transmission based on an uplink grant indicated in Msg2 andMsg4 may be for contention resolution.

The base station may transmit one or more RRC messages comprisingconfiguration parameters of the random access parameters. The randomaccess parameters may indicate radio resources (e.g., time-frequencyresources) for transmission of the random access preamble (e.g., Msg1),configuration index, one or more parameters for determining the power ofthe random access preamble (e.g., a power ramping parameter, a preamblereceived target power, etc.), a parameter indicating maximum number ofpreamble transmission, RAR window for monitoring RAR, cell-specificrandom access parameters and UE specific random access parameters. TheUE-specific random access parameters may indicate one or more PRACHoccasions for random access preamble (e.g., Msg1) transmissions. Therandom access parameters may indicate association between the PRACHoccasions and one or more reference signals (e.g., SSB or CSI-RS). Therandom access parameters may further indicate association between therandom access preambles and one or more reference signals (e.g., SBB orCSI-RS). The UE may use one or more reference signals (e.g., SSB(s) orCSI-RS(s)) and may determine a random access preamble to use for Msg1transmission based on the association between the random accesspreambles and the one or more reference signals. The UE may use one ormore reference signals (e.g., SSB(s) or CSI-RS(s)) and may determine thePRACH occasion to use for Msg1 transmission based on the associationbetween the PRACH occasions and the reference signals. The UE mayperform a retransmission of the random access preamble if no response isreceived with the RAR window following the transmission of the preamble.UE may use a higher transmission power for retransmission of thepreamble. UE may determine the higher transmission power of the preamblebased on the power ramping parameter.

Msg2 is for transmission of RAR by the base station. Msg2 may comprise aplurality of RARs corresponding to a plurality of random accesspreambles transmitted by a plurality of UEs. Msg2 may be associated witha random access temporary radio identifier (RA-RNTI) and may be receivedin a common search space of the UE. The RA-RNTI may be based on thePRACH occasion (e.g., time and frequency resources of a PRACH) in whicha random access preamble is transmitted. RAR may comprise a timingadvance command for uplink timing adjustment at the UE, an uplink grantfor transmission of Msg3 and a temporary C-RNTI. In response to thesuccessful reception of Msg2, the UE may transmit the Msg3. Msg3 andMsg4 may enable contention resolution in case of CBRA. In a CBRA, aplurality of UEs may transmit the same random access preamble and mayconsider the same RAR as being corresponding to them. UE may include adevice identifier in Msg3 (e.g., a C-RNTI, temporary C-RNTI or other UEidentity). Base station may transmit the Msg4 with a PDSCH and UE mayassume that the contention resolution is successful in response to thePDSCH used for transmission of Msg4 being associated with the UEidentifier included in Msg3.

FIG. 12B shows an example of a contention-free random access (CFRA)process. Msg 1 (random access preamble) and Msg 2 (random accessresponse) in FIG. 12B for CFRA may be analogous to Msg 1 and Msg 2 inFIG. 12A for CBRA. In an example, the CFRA procedure may be initiated inresponse to a PDCCH order from a base station. The PDCCH order forinitiating the CFRA procedure by the wireless device may be based on aDCI having a first format (e.g., format 1_0). The DCI for the PDCCHorder may comprise a random access preamble index, an UL/SUL indicatorindicating an uplink carrier of a cell (e.g., normal uplink carrier orsupplementary uplink carrier) for transmission of the random accesspreamble, a SS/PBCH index indicating the SS/PBCH that may be used todetermine a RACH occasion for PRACH transmission, a PRACH mask indexindicating the RACH occasion associated with the SS/PBCH indicated bythe SS/PBCH index for PRACH transmission, etc. In an example, the CFRAprocess may be started in response to a beam failure recovery process.The wireless device may start the CFRA for the beam failure recoverywithout a command (e.g., PDCCH order) from the base station and by usingthe wireless device dedicated resources.

FIG. 12C shows an example of a two-step random access process comprisingtwo messages exchanged between a wireless device and a base station. MsgA may be transmitted by the wireless device to the base station and maycomprise one or more transmissions of a preamble and/or one or moretransmissions of a transport block. The transport block in Msg A and Msg3 in FIG. 12A may have similar and/or equivalent contents. The transportblock of Msg A may comprise data and control information (e.g., SR, HARQfeedback, etc.). In response to the transmission of Msg A, the wirelessdevice may receive Msg B from the base station. Msg B in FIG. 12C andMsg 2 (e.g., RAR) illustrated in FIGS. 12A and 12B may have similarand/or equivalent content.

The base station may periodically transmit synchronization signals(SSs), e.g., primary SS (PSS) and secondary SS (SSS) along with PBCH oneach NR cell. The PSS/SSS together with PBCH is jointly referred to as aSS/PBCH block. The SS/PBCH block enables a wireless device to find acell when entering to the mobile communications network or find newcells when moving within the network. The SS/PBCH block spans four OFDMsymbols in time domain. The PSS is transmitted in the first symbol andoccupies 127 subcarriers in frequency domain. The SSS is transmitted inthe third OFDM symbol and occupies the same 127 subcarriers as the PSS.The are eight and nine empty subcarriers on each side of the SSS. ThePBCH is transmitted on the second OFDM symbol occupying 240 subcarriers,the third OFDM symbol occupying 48 subcarriers on each side of the SSS,and on the fourth OFDM symbol occupying 240 subcarriers. Some of thePBCH resources indicated above may be used for transmission of thedemodulation reference signal (DMRS) for coherent demodulation of thePBCH. The SS/PBCH block is transmitted periodically with a periodranging from 5 ms to 160 ms. For initial cell search or for cell searchduring inactive/idle state, a wireless device may assume that that theSS/PBCH block is repeated at least every 20 ms.

In NR, transmissions using of antenna arrays, with many antennaelements, and beamforming plays an important role specially in higherfrequency bands. Beamforming enables higher capacity by increasing thesignal strength (e.g., by focusing the signal energy in a specificdirection) and by lowering the amount interference received at thewireless devices. The beamforming techniques may generally be divided toanalog beamforming and digital beamforming techniques. With digitalbeamforming, signal processing for beamforming is carried out in thedigital domain before digital-to-analog conversion and detailed controlof both amplitude and phase of different antenna elements may bepossible. With analog beamforming, the signal processing for beamformingis carried out in the analog domain and after the digital to analogconversion. The beamformed transmissions may be in one direction at atime. For example, the wireless devices that are in different directionsrelative to the base station may receive their downlink transmissions atdifferent times. For analog receiver-side beamforming, the receiver mayfocus its receiver beam in one direction at a time.

In NR, the base station may use beam sweeping for transmission ofSS/PBCH blocks. The SS/PBCH blocks may be transmitted in different beamsusing time multiplexing. The set of SS/PBCH blocks that are transmittedin one beam sweep may be referred to as a SS/PBCH block set. The periodof PBCH/SSB block transmission may be a time duration between a SS/PBCHblock transmission in a beam and the next SS/PBCH block transmission inthe same beam. The period of SS/PBCH block is, therefore, also theperiod of the SS/PBCH block set.

FIG. 13A shows example time and frequency structure of SS/PBCH blocksand their associations with beams in accordance with several of variousembodiments of the present disclosure. In this example, a SS/PBCH block(also referred to as SSB) set comprise L SSBs wherein an SSB in the SSBset is associated with (e.g., transmitted in) one of L beams of a cell.The transmission of SBBs of an SSB set may be confined within a 5 msinterval, either in a first half-frame or a second half-frame of a 10 msframe. The number of SSBs in an SSB set may depend on the frequency bandof operation. For example, the number of SSBs in a SSB set may be up tofour SSBs in frequency bands below 3 GHz enabling beam sweeping of up tofour beams, up to eight SSBs in frequency bands between 3 GHz and 6 GHzenabling beam sweeping of up to eight beams, and up to sixty four SSBsin higher frequency bands enabling beam sweeping of up to sixty fourbeams. The SSs of an SSB may depend on a physical cell identity (PCI) ofthe cell and may be independent of which beam of the cell is used fortransmission of the SSB. The PBCH of an SSB may indicate a time indexparameter and the wireless device may determine the relative position ofthe SSB within the SSB set using the time index parameter. The wirelessdevice may use the relative position of the SSB within an SSB set fordetermining the frame timing and/or determining RACH occasions for arandom access process.

A wireless device entering the mobile communications network may firstsearch for the PSS. After detecting the PSS, the wireless device maydetermine the synchronization up to the periodicity of the PSS. Bydetecting the PSS, the wireless device may determine the transmissiontiming of the SSS. The wireless device may determine the PCI of the cellafter detecting the SSS. The PBCH of a SS/PBCH block is a downlinkphysical channel that carries the MIB. The MIB may be used by thewireless device to obtain remaining system information (RMSI) that isbroadcast by the network. The RMSI may include System Information Block1 (SIB1) that contains information required for the wireless device toaccess the cell.

As discussed earlier, the wireless device may determine a time indexparameter from the SSB. The PBCH comprises a half-frame parameterindicating whether the SSB is in the first 5 ms half or the second 5 mshalf of a 10 ms frame. The wireless device may determine the frameboundary using the time index parameter and the half-frame parameter. Inaddition, the PBCH may comprise a parameter indicating the system framenumber (SFN) of the cell.

The base station may transmit CSI-RS and a UE may measure the CSI-RS toobtain channel state information (CSI). The base station may configurethe CSI-RS in a UE-specific manner. In some scenarios, same set ofCSI-RS resources may be configured for multiple UEs and one or moreresource elements of a CSI-RS resource may be shared among multiple UEs.A CSI-RS resource may be configured such that it does not collide with aCORESET configured for the wireless device and/or with a DMRS of a PDSCHscheduled for the wireless device and/or transmitted SSBs. The UE maymeasure one or more CSI-RSs configured for the UE and may generate a CSIreport based on the CSI-RS measurements and may transmit the CSI reportto the base station for scheduling, link adaptation and/or otherpurposes.

NR supports flexible CSI-RS configurations. A CSI-RS resource may beconfigured with single or multiple antenna ports and with configurabledensity. Based on the number of configured antenna ports, a CSI-RSresource may span different number of OFDM symbols (e.g., 1, 2, and 4symbols). The CSI-RS may be configured for a downlink BWP and may usethe numerology of the downlink BWP. The CSI-RS may be configured tocover the full bandwidth of the downlink BWP or a portion of thedownlink BWP. In some case, the CSI-RS may be repeated in every resourceblock of the CSI-RS bandwidth, referred to as CSI-RS with density equalto one. In some cases, the CSI-RS may be configured to be repeated inevery other resource block of the CSI-RS bandwidth. CSI-RS may benon-zero power (NZP) CSI-RS or zero-power (ZP) CSI-RS.

The base station may configure a wireless device with one or more setsof NZP CSI-RS resources. The base station may configure the wirelessdevice with a NZP CSI-RS resource set using an RRC information element(IE) NZP-CSI-RS-ResourceSet indicating a NZP CSI-RS resource setidentifier (ID) and parameters specific to the NZP CSI-RS resource set.An NZP CSI-RS resource set may comprise one or more CSI-RS resources. AnNZP CSI-RS resource set may be configured as part of the CSI measurementconfiguration.

The CSI-RS may be configured for periodic, semi-persistent or aperiodictransmission. In case of the periodic and semi-persistent CSI-RSconfigurations, the wireless device may be configured with a CSIresource periodicity and offset parameter that indicate a periodicityand corresponding offset in terms of number of slots. The wirelessdevice may determine the slots that the CSI-RSs are transmitted. Forsemi-persistent CSI-RS, the CSI-RS resources for CSI-RS transmissionsmay be activated and deactivated by using a semi-persistent (SP) CSI-CSIResource Set Activation/Deactivation MAC CE. In response to receiving aMAC CE indicating activation of semi-persistent CSI-RS resources, thewireless device may assume that the CSI-RS transmissions will continueuntil the CSI-RS resources for CSI-RS transmissions are activated.

As discussed before, CSI-RS may be configured for a wireless device asNZP CSI-RS or ZP CSI-RS. The configuration of the ZP CSI-RS may besimilar to the NZP CSI-RS with the difference that the wireless devicemay not carry out measurements for the ZP CSI-RS. By configuring ZPCSI-RS, the wireless device may assume that a scheduled PDSCH thatincludes resource elements from the ZP CSI-RS is rate matched aroundthose ZP CSI-RS resources. For example, a ZP CSI-RS resource configuredfor a wireless device may be an NZP CSI-RS resource for another wirelessdevice. For example, by configuring ZP CSI-RS resources for the wirelessdevice, the base station may indicate to the wireless device that thePDSCH scheduled for the wireless device is rate matched around the ZPCSI-RS resources.

A base station may configure a wireless device with channel stateinformation interference measurement (CSI-IM) resources. Similar to theCSI-RS configuration, configuration of locations and density of CSI-IMresources may be flexible. The CSI-IM resources may be periodic(configured with a periodicity), semi-persistent (configured with aperiodicity and activated and deactivated by MAC CE) or aperiodic(triggered by a DCI).

Tracking reference signals (TRSs) may be configured for a wirelessdevice as a set of sparse reference signals to assist the wireless intime and frequency tracking and compensating time and frequencyvariations in its local oscillator. The wireless device may further usethe TRSs for estimating channel characteristics such as delay spread ordoppler frequency. The base station may use a CSI-RS configuration forconfiguring TRS for the wireless device. The TRS may be configured as aresource set comprising multiple periodic NZP CSI-RS resources.

A base station may configure a UE and the UE may transmit soundingreference signals (SRSs) to enable uplink channel sounding/estimation atthe base station. The SRS may support up to four antenna ports and maybe designed with low cubic metric enabling efficient operation of thewireless device amplifier. The SRS may span one or more (e.g., one, twoor four) consecutive OFDM symbols in time domain and may be locatedwithin the last n (e.g., six) symbols of a slot. In the frequencydomain, the SRS may have a structure that is referred to as a combstructure and may be transmitted on every Nth subcarrier. Different SRStransmissions from different wireless devices may have different combstructures and may be multiplexed in frequency domain.

A base station may configure a wireless device with one or more SRSresource sets and an SRS resource set may comprise one or more SRSresources. The SRS resources in an SRS resources set may be configuredfor periodic, semi-persistent or aperiodic transmission. The periodicSRS and the semi-persistent SRS resources may be configured withperiodicity and offset parameters. The Semi-persistent SRS resources ofa configured semi-persistent SRS resource set may be activated ordeactivated by a semi-persistent (SP) SRS Activation/Deactivation MACCE. The set of SRS resources included in an aperiodic SRS resource setmay be activated by a DCI. A value of a field (e.g., an SRS requestfield) in the DCI may indicate activation of resources in an aperiodicSRS resource set from a plurality of SRS resource sets configured forthe wireless device.

An antenna port may be associated with one or more reference signals.The receiver may assume that the one or more reference signals,associated with the antenna port, may be used for estimating channelcorresponding to the antenna port. The reference signals may be used toderive channel state information related to the antenna port. Twoantenna ports may be referred to as quasi co-located if characteristics(e.g., large-scale properties) of the channel over which a symbol isconveyed on one antenna port may be inferred from the channel over whicha symbol is conveyed from another antenna port. For example, a UE mayassume that radio channels corresponding to two different antenna portshave the same large-scale properties if the antenna ports are specifiedas quasi co-located. In some cases, the UE may assume that two antennaports are quasi co-located based on signaling received from the basestation. Spatial quasi-colocation (QCL) between two signals may be, forexample, due to the two signals being transmitted from the same locationand in the same beam. If a receive beam is good for a signal in a groupof signals that are spatially quasi co-located, it may be assumed alsobe good for the other signals in the group of signals.

The CSI-RS in the downlink and the SRS in uplink may serve asquasi-location (QCL) reference for other physical downlink channels andphysical uplink channels, respectively. For example, a downlink physicalchannel (e.g., PDSCH or PDCCH) may be spatially quasi co-located with adownlink reference signal (e.g., CSI-RS or SSB). The wireless device maydetermine a receive beam based on measurement on the downlink referencesignal and may assume that the determined received beam is also good forreception of the physical channels (e.g., PDSCH or PDCCH) that arespatially quasi co-located with the downlink reference signal.Similarly, an uplink physical channel (e.g., PUSCH or PUCCH) may bespatially quasi co-located with an uplink reference signal (e.g., SRS).The base station may determine a receive beam based on measurement onthe uplink reference signal and may assume that the determined receivedbeam is also good for reception of the physical channels (e.g., PUSCH orPUCCH) that are spatially quasi co-located with the uplink referencesignal.

The Demodulation Reference Signals (DM-RSs) enables channel estimationfor coherent demodulation of downlink physical channels (e.g., PDSCH,PDCCH and PBH) and uplink physical channels (e.g., PUSCH and PUCCH). TheDM-RS may be located early in the transmission (e.g., front-loadedDM-RS) and may enable the receiver to obtain the channel estimate earlyand reduce the latency. The time-domain structure of the DM-RS (e.g.,symbols wherein the DM-RS are located in a slot) may be based ondifferent mapping types.

The Phase Tracking Reference Signals (PT-RSs) enables tracking andcompensation of phase variations across the transmission duration. Thephase variations may be, for example, due to oscillator phase noise. Theoscillator phase noise may become more sever in higher frequencies(e.g., mmWave frequency bands). The base station may configure the PT-RSfor uplink and/or downlink. The PT-RS configuration parameters mayindicate frequency and time density of PT-RS, maximum number of ports(e.g., uplink ports), resource element offset, configuration of uplinkPT-RS without transform precoder (e.g., CP-OFDM) or with transformprecoder (e.g., DFT-s-OFDM), etc. The subcarrier number and/or resourceblocks used for PT-RS transmission may be based on the C-RNTI of thewireless device to reduce risk of collisions between PT-RSs of wirelessdevices scheduled on overlapping frequency domain resources.

FIG. 13B shows example time and frequency structure of CSI-RSs and theirassociation with beams in accordance with several of various embodimentsof the present disclosure. A beam of the L beams shown in FIG. 13B maybe associated with a corresponding CSI-RS resource. The base station maytransmit the CSI-RSs using the configured CSI-RS resources and a UE maymeasure the CSI-RSs (e.g., received signal received power (RSRP) of theCSI-RSs) and report the CSI-RS measurements to the base station based ona reporting configuration. For example, the base station may determineone or more transmission configuration indication (TCI) states and mayindicate the one or more TCI states to the UE (e.g., using RRCsignaling, a MAC CE and/or a DCI). Based on the one or more TCI statesindicated to the UE, the UE may determine a downlink receive beam andreceive downlink transmissions using the receive beam. In case of a beamcorrespondence, the UE may determine a spatial domain filter of atransmit beam based on spatial domain filter of a corresponding receivebeam. Otherwise, the UE may perform an uplink beam selection procedureto determine the spatial domain filter of the transmit beam. The UE maytransmit one or more SRSs using the SRS resources configured for the UEand the base station may measure the SRSs and determine/select thetransmit beam for the UE based the SRS measurements. The base stationmay indicate the selected beam to the UE. The CSI-RS resources shown inFIG. 13B may be for one UE. The base station may configure differentCSI-RS resources associated with a given beam for different UEs by usingfrequency division multiplexing.

A base station and a wireless device may perform beam managementprocedures to establish beam pairs (e.g., transmit and receive beams)that jointly provide good connectivity. For example, in the downlinkdirection, the UE may perform measurements for a beam pair and estimatechannel quality for a transmit beam by the base station (or atransmission reception point (TRP) more generally) and the receive beamby the UE. The UE may transmit a report indicating beam pair qualityparameters. The report may comprise one or more parameters indicatingone or more beams (e.g., a beam index, an identifier of reference signalassociated with a beam, etc.), one or more measurement parameters (e.g.,RSRP), a precoding matrix indicator (PMI), a channel quality indicator(CQI), and/or a rank indicator (RI).

FIG. 14A, FIG. 14B and FIG. 14C show example beam management processes(referred to as P1, P2 and P3, respectively) in accordance with severalof various embodiments of the present disclosure. The P1 process shownin FIG. 14A may enable, based on UE measurements, selection of a basestation (or TRP more generally) transmit beam and/or a wireless devicereceive beam. The TRP may perform a beam sweeping procedure where theTRP may sequentially transmit reference signals (e.g., SSB and/orCSI-RS) on a set of beams and the UE may select a beam from the set ofbeams and may report the selected beam to the TRP. The P2 procedure asshown in FIG. 14B may be a beam refinement procedure. The selection ofthe TRP transmit beam and the UE receive beam may be regularlyreevaluated due to movements and/or rotations of the UE or movement ofother objects. In an example, the base station may perform the beamsweeping procedure over a smaller set of beams and the UE may select thebest beam over the smaller set. In an example, the beam shape may benarrower compared to beam selected based on the P1 procedure. Using theP3 procedure as shown in FIG. 14C, the TRP may fix its transmit beam andthe UE may refine its receive beam.

A wireless device may receive one or more messages from a base station.The one or more messages may comprise one or more RRC messages. The oneor more messages may comprise configuration parameters of a plurality ofcells for the wireless device. The plurality of cells may comprise aprimary cell and one or more secondary cells. For example, the pluralityof cells may be provided by a base station and the wireless device maycommunicate with the base station using the plurality of cells. Forexample, the plurality of cells may be provided by multiple base station(e.g., in case of dual and/or multi-connectivity). The wireless devicemay communicate with a first base station, of the multiple basestations, using one or more first cells of the plurality of cells. Thewireless device may communicate with a second base station of themultiple base stations using one or more second cells of the pluralityof cells.

The one or more messages may comprise configuration parameters used forprocesses in physical, MAC, RLC, PCDP, SDAP, and/or RRC layers of thewireless device. For example, the configuration parameters may includevalues of timers used in physical, MAC, RLC, PCDP, SDAP, and/or RRClayers. For example, the configuration parameters may include parametersfor configurating different channels (e.g., physical layer channel,logical channels, RLC channels, etc.) and/or signals (e.g., CSI-RS, SRS,etc.).

Upon starting a timer, the timer may start running until the timer isstopped or until the timer expires. A timer may be restarted if it isrunning. A timer may be started if it is not running (e.g., after thetimer is stopped or after the timer expires). A timer may be configuredwith or may be associated with a value (e.g., an initial value). Thetimer may be started or restarted with the value of the timer. The valueof the timer may indicate a time duration that the timer may be runningupon being started or restarted and until the timer expires. Theduration of a timer may not be updated until the timer is stopped orexpires (e.g., due to BWP switching). This specification may disclose aprocess that includes one or more timers. The one or more timers may beimplemented in multiple ways. For example, a timer may be used by thewireless device and/or base station to determine a time window [t1, t2],wherein the timer is started at time t1 and expires at time t2 and thewireless device and/or the base station may be interested in and/ormonitor the time window [t1, t2], for example to receive a specificsignaling. Other examples of implementation of a timer may be provided.

FIG. 15 shows example components of a wireless device and a base stationthat are in communication via an air interface in accordance withseveral of various embodiments of the present disclosure. The wirelessdevice 1502 may communicate with the base station 1542 over the airinterface 1532. The wireless device 1502 may include a plurality ofantennas. The base station 1542 may include a plurality of antennas. Theplurality of antennas at the wireless device 1502 and/or the basestation 1542 enables different types of multiple antenna techniques suchas beamforming, single-user and/or multi-user MIMO, etc.

The wireless device 1502 and the base station 1542 may have one or moreof a plurality of modules/blocks, for example RF front end (e.g., RFfront end 1530 at the wireless device 1502 and RF front end 1570 at thebase station 1542), Data Processing System (e.g., Data Processing System1524 at the wireless device 1502 and Data Processing System 1564 at thebase station 1542), Memory (e.g., Memory 1512 at the wireless device1502 and Memory 1542 at the base station 1542). Additionally, thewireless device 1502 and the base station 1542 may have othermodules/blocks such as GPS (e.g., GPS 1514 at the wireless device 1502and GPS 1554 at the base station 1542).

An RF front end module/block may include circuitry between antennas anda Data Processing System for proper conversion of signals between thesetwo modules/blocks. An RF front end may include one or more filters(e.g., Filter(s) 1526 at RF front end 1530 or Filter(s) 1566 at the RFfront end 1570), one or more amplifiers (e.g., Amplifier(s) 1528 at theRF front end 1530 and Amplifier(s) 1568 at the RF front end 1570). TheAmplifier(s) may comprise power amplifier(s) for transmission andlow-noise amplifier(s) (LNA(s)) for reception.

The Data Processing System 1524 and the Data Processing System 1564 mayprocess the data to be transmitted or the received signals byimplementing functions at different layers of the protocol stack such asPHY, MAC, RLC, etc. Example PHY layer functions that may be implementedby the Data Processing System 1524 and/or 1564 may include forward errorcorrection, interleaving, rate matching, modulation, precoding, resourcemapping, MIMO processing, etc. Similarly, one or more functions of theMAC layer, RLC layer and/or other layers may be implemented by the DataProcessing System 1524 and/or the Data Processing System 1564. One ormore processes described in the present disclosure may be implemented bythe Data Processing System 1524 and/or the Data Processing System 1564.A Data Processing System may include an RF module (RF module 1516 at theData Processing System 1524 and RF module 1556 at the Data ProcessingSystem 1564) and/or a TX/RX processor (e.g., TX/RX processor 1518 at theData Processing System 1524 and TX/RX processor 1558 at the DataProcessing System 1566) and/or a central processing unit (CPU) (e.g.,CPU 1520 at the Data Processing System 1524 and CPU 1560 at the DataProcessing System 1564) and/or a graphical processing unit (GPU) (e.g.,GPU 1522 at the Data Processing System 1524 and GPU 1562 at the DataProcessing System 1564).

The Memory 1512 may have interfaces with the Data Processing System 1524and the Memory 1552 may have interfaces with Data Processing System1564, respectively. The Memory 1512 or the Memory 1552 may includenon-transitory computer readable mediums (e.g., Storage Medium 1510 atthe Memory 1512 and Storage Medium 1550 at the Memory 1552) that maystore software code or instructions that may be executed by the DataProcessing System 1524 and Data Processing System 1564, respectively, toimplement the processes described in the present disclosure. The Memory1512 or the Memory 1552 may include random-access memory (RAM) (e.g.,RAM 1506 at the Memory 1512 or RAM 1546 at the Memory 1552) or read-onlymemory (ROM) (e.g., ROM 1508 at the Memory 1512 or ROM 1548 at theMemory 1552) to store data and/or software codes.

The Data Processing System 1524 and/or the Data Processing System 1564may be connected to other components such as a GPS module 1514 and a GPSmodule 1554, respectively, wherein the GPS module 1514 and a GPS module1554 may enable delivery of location information of the wireless device1502 to the Data Processing System 1524 and location information of thebase station 1542 to the Data Processing System 1564. One or more otherperipheral components (e.g., Peripheral Component(s) 1504 or PeripheralComponent(s) 1544) may be configured and connected to the dataProcessing System 1524 and data Processing System 1564, respectively.

In example embodiments, a wireless device may be configured withparameters and/or configuration arrangements. For example, theconfiguration of the wireless device with parameters and/orconfiguration arrangements may be based on one or more control messagesthat may be used to configure the wireless device to implement processesand/or actions. The wireless device may be configured with theparameters and/or the configuration arrangements regardless of thewireless device being in operation or not in operation. For example,software, firmware, memory, hardware and/or a combination thereof and/oralike may be configured in a wireless device regardless of the wirelessdevice being in operation or not operation. The configured parametersand/or settings may influence the actions and/or processes performed bythe wireless device when in operation.

In example embodiments, a wireless device may receive one or moremessage comprising configuration parameters. For example, the one ormore messages may comprise radio resource control (RRC) messages. Aparameter of the configuration parameters may be in at least one of theone or more messages. The one or more messages may comprise informationelement (IEs). An information element may be a structural element thatincludes single or multiple fields. The fields in an IE may beindividual contents of the IE. The terms configuration parameter, IE andfield may be used equally in this disclosure. The IEs may be implementedusing a nested structure, wherein an IE may include one or more otherIEs and an IE of the one or more other IEs may include one or moreadditional IEs. With this structure, a parent IE contains all theoffspring IEs as well. For example, a first IE containing a second IE,the second IE containing a third IE, and the third IE containing afourth IE may imply that the first IE contains the third IE and thefourth IE.

The amount of licensed spectrum available for an operator to meet thedemands may not be sufficient and obtaining licensed spectrum may becostly. Unlicensed spectrum is freely available subject to a set ofrules, for example rules on maximum transmission power. Since theunlicensed spectrum is freely available, the interference situation maybe more unpredictable compared to licensed spectrum. Achievingquality-of-service may be more challenging in unlicensed spectrum. WLANsand Bluetooth are examples of communication systems exploitingunlicensed spectrum in the lower-frequency range, e.g., 2.4 GHz or 5GHz.

Some of the frequency bands used by an NR communications system may beunlicensed (e.g., in lower and/or higher frequency bands). Differentdeployment scenarios may be used in example embodiments. Exampledeployment scenarios include: carrier aggregation between licensed bandNR (for example for PCell) and unlicensed band NR (NR-U) (for examplefor SCell), wherein NR-U SCell may have both DL and UL or may beDL-only; dual connectivity between licensed band LTE (e.g., PCell) andNR-U (e.g., PSCell); standalone NR-U, wherein PCell and SCell may beboth in unlicensed bands; an NR cell with DL in unlicensed band and ULin licensed band; and dual connectivity between licensed band NR (e.g.,PCell) and NR-U (e.g., PSCell).

In an example, the licensed spectrum may be used to provide wide-areacoverage and quality-of-service guarantees, with unlicensed spectrumused as a local-area complement to increase user data rates and overallcapacity without compromising on overall coverage, availability, andreliability. This may be referred to as License-Assisted Access (LAA).

In an example, to enable fair sharing of unlicensed spectra with otheroperators and/or systems (e.g., Wi-Fi), several mechanisms may be usedin example embodiments. Example mechanisms may include dynamic frequencyselection (DFS), where a network node may search and find a part of theunlicensed spectrum with low load. Example embodiments may employlisten-before-talk (LBT) based on example channel access procedures,where the transmitter ensures there are no ongoing transmissions on thecarrier frequency prior to transmitting.

In an example, a channel may refer to a carrier or a part of a carrieron which a channel access procedure is performed. A channel accessprocedure is a procedure based on sensing that evaluates theavailability of a channel for performing transmissions on. The basicunit for sensing may be a sensing slot with a duration T_(sl)=9 us. Thesensing slot duration T_(sl) may be considered to be idle if a basestation or a wireless device senses the channel during the sensing slotduration, and determines that the detected power for at least a portion(e.g., 4 us) within the sensing slot duration is less than an energydetection threshold (e.g., X_(Thresh)). Otherwise, the sensing slotduration T_(sl) may be considered to be busy.

A Channel Occupancy Time (COT) may refer to the total time for whicheNB/gNB/UE and eNB/gNB/UEs sharing the channel occupancy can performtransmission(s) on a channel after an eNB/gNB/UE performs thecorresponding channel access procedures. For determining a ChannelOccupancy Time, if a transmission gap is less than 25 us, the gapduration may be counted in the channel occupancy time. A channeloccupancy time may be shared for transmission between a base station andthe corresponding wireless device(s). A DL transmission burst may bedefined as a set of transmissions from a base station without gapsgreater than 16 us. Transmissions from a base station separated by a gapof more than 16 us may be considered as separate DL transmission bursts.An UL transmission burst may be defined as a set of transmissions from aUE without gaps greater than 16 us. Transmissions from a wireless deviceseparated by a gap of more than 16 us may be considered as separate ULtransmission.

In an example, a wireless device may access a channel on which uplinktransmission(s) are performed according to an uplink channel accessprocedure (e.g., one of Type 1 or Type 2 uplink channel accessprocedures). If an uplink grant scheduling a PUSCH transmissionindicates Type 1 channel access procedure, the wireless device may useType 1 channel access procedure for transmitting transmissions includingthe PUSCH transmission. A wireless device may use Type 1 channel accessprocedure for transmitting transmissions including autonomous PUSCHtransmission on configured uplink resources. If an uplink grantscheduling a PUSCH transmission indicates Type 2 channel accessprocedure, the wireless device may use Type 2 channel access procedurefor transmitting transmissions including the PUSCH transmission. Awireless device may use Type 1 channel access procedure for transmittingSRS transmissions not including a PUSCH transmission. In an example,uplink channel access priority class p=1, as shown in FIG. 16, may beused for SRS transmissions not including a PUSCH.

In an example, if a wireless device is scheduled by a base station totransmit PUSCH and SRS in contiguous transmissions without gaps inbetween, and if the wireless device cannot access the channel for PUSCHtransmission, the wireless device may attempt to make SRS transmissionaccording to uplink channel access procedures for SRS transmission.

In an example, a wireless device may use Type 1 channel access procedurefor PUCCH only transmissions or PUSCH only transmissions without UL-SCHwith UL channel access priority class p=1 in FIG. 16.

In an example, a wireless device may use Type 1 channel access procedurefor transmissions related to random access procedure with uplink channelaccess priority class p=1 in FIG. 16.

In an example, the total duration of autonomous uplink transmission(s)obtained by the channel access procedure, including the following DLtransmission if the UE sets ‘COT sharing indication’ in AUL-UCI to ‘1’in a subframe within the autonomous uplink transmission(s), may notexceed T_(ulmcot,p), where T_(ulmcot,p) is given in FIG. 16.

In an example, a wireless device may detect ‘UL duration and offset’field in a DCI. If the UL duration and offset’ field indicates an ‘ULoffset’ l and an ‘UL duration’ d for subframe n, then the scheduled UEmay use channel access Type 2 for transmissions in subframes n+l+i wherei=0, 1, . . . d−1, irrespective of the channel access Type signalled inthe UL grant for those subframes, if the end of wireless devicetransmission occurs in or before subframe n+l+d−1.

In an example, if the ‘UL duration and offset’ field indicates an ‘ULoffset’ l and an ‘UL duration’ d for subframe n and the ‘COT sharingindication for AUL’ field is set to ‘1’, a UE configured with autonomousUL may use channel access Type 2 for autonomous UL transmissionscorresponding to any priority class in subframes n+l+i where i=0, 1, . .. d−1, if the end of wireless device autonomous UL transmission occursin or before subframe n+l+d−1 and the autonomous UL transmission betweenn+l and n+l+d−1 may be contiguous.

In an example, if the ‘UL duration and offset’ field indicates an ‘ULoffset’ l and an ‘UL duration’ d for subframe n and the ‘COT sharingindication for AUL’ field is set to ‘0’, then a UE configured withautonomous UL may not transmit autonomous UL in subframes n+l+i wherei=0, 1, . . . d−1.

In an example, for contiguous UL transmission(s), if a wireless deviceis scheduled to transmit a set of w UL transmissions including PUSCHusing a PDCCH DCI format, and if the wireless device cannot access thechannel for a transmission in the set prior to the last transmission,the wireless device may attempt to transmit the next transmissionaccording to the channel access type indicated in the DCI.

In an example, for contiguous uplink transmission(s), if a wirelessdevice is scheduled to transmit a set of w consecutive uplinktransmissions without gaps including PUSCH using one or more PDCCH DCIformats and the wireless device transmits one of the scheduled uplinktransmissions in the set after accessing the channel according to one ofuplink channel access procedures (e.g., Type 1 or Type 2), the wirelessdevice may continue transmission the remaining uplink transmissions inthe set, if any.

In an example, for contiguous UL transmission(s), a wireless device maynot be expected to be indicated with different channel access types forany consecutive UL transmissions without gaps in between thetransmissions.

In an example, for uplink transmission(s) with multiple startingpositions scheduled by a base station, if a wireless device is scheduledby an base station to transmit transmissions including PUSCH Mode 1using the Type 1 channel access procedure indicated in DCI, and if thewireless device cannot access the channel for a transmission accordingto the PUSCH starting position indicated in the DCI, the wireless devicemay attempt to make a transmission at symbol 7 in the same subframeaccording to Type 1 channel access procedure. In an example, there maybe no limit on the number of attempts the UE can make using Type 1channel access procedure.

In an example, for uplink transmission(s) with multiple startingpositions scheduled by a base station, if a wireless device is scheduledby a base station to transmit transmissions including PUSCH Mode 1 usingthe Type 2 channel access procedure indicated in DCI, and if thewireless device cannot access the channel for a transmission accordingto the PUSCH starting position indicated in the DCI, the wireless devicemay attempt to make a transmission at symbol 7 in the same subframe andaccording to Type 2 channel access procedure. The number of attempts thewireless device may make within the consecutively scheduled subframesincluding the transmission may be limited to w+1, where w may be thenumber of consecutively scheduled subframes using Type 2 channel accessprocedure.

In an example, for contiguous uplink transmissions(s) including atransmission pause, if the wireless is scheduled to transmit a set of wconsecutive uplink transmissions without gaps using one or more PDCCHDCI formats, and if the wireless device has stopped transmitting duringor before of one of these uplink transmissions in the set and prior tothe last uplink transmission in the set, and if the channel is sensed bythe wireless device to be continuously idle after the wireless devicehas stopped transmitting, the wireless device may transmit a lateruplink transmission in the set using Type 2 channel access procedure. Ifthe channel sensed by the wireless device is not continuously idle afterthe wireless device has stopped transmitting, the wireless device maytransmit a later uplink transmission in the set using Type 1 channelaccess procedure with the uplink channel access priority class indicatedin the DCI corresponding to the uplink transmission.

In an example, for uplink transmission(s) following configured uplinktransmission(s), if the wireless device is scheduled by a base stationto transmit on channel c_(i) by a uplink grant received on channelc_(j), i≠j, and if the wireless device is transmitting using autonomousuplink on channel c_(i), the wireless device may terminate the ongoingPUSCH transmissions using the autonomous uplink at least one subframebefore the uplink transmission according to the received uplink grant.

In an example, if the wireless device is scheduled by an uplink grantreceived from a base station on a channel to transmit a PUSCHtransmission(s) starting from subframe n on the same channel using Type1 channel access procedure and if at least for the first scheduledsubframe occupies N_(RB) ^(UL) resource blocks and the indicated ‘PUSCHstarting position is OFDM symbol zero, and if the wireless device startsautonomous uplink transmissions before subframe n using Type 1 channelaccess procedure on the same channel, the wireless device may transmituplink transmission(s) according to the received uplink grant fromsubframe n without a gap, if the priority class value of the performedchannel access procedure is larger than or equal to priority class valueindicated in the uplink grant, and the autonomous uplink transmission inthe subframe preceding subframe n may end at the last OFDM symbol of thesubframe regardless of the higher layer parameter endingSymbolAUL. Thesum of the lengths of the autonomous uplink transmission(s) and thescheduled uplink transmission(s) may not exceed the maximum channeloccupancy time corresponding to the priority class value used to performthe autonomous uplink channel access procedure. Otherwise, the wirelessdevice may terminate the ongoing autonomous uplink transmission at leastone subframe before the start of the uplink transmission according tothe received uplink grant on the same channel.

In an example, if a wireless device receives an uplink grant and a DCIindicating a PUSCH transmission using Type 1 channel access procedure,and if the wireless device has an ongoing Type 1 channel accessprocedure before the PUSCH transmission starting time, if the uplinkchannel access priority class value p₁ used for the ongoing Type 1channel access procedure is same or larger than the uplink channelaccess priority class value p₂ indicated in the DCI, the wireless devicemay transmit the PUSCH transmission in response to the uplink grant byaccessing the channel by using the ongoing Type 1 channel accessprocedure.

In an example, if a wireless device receives an uplink grant and a DCIindicating a PUSCH transmission using Type 1 channel access procedure,and if the wireless device has an ongoing Type 1 channel accessprocedure before the PUSCH transmission starting time, if the uplinkchannel access priority class value p₁ used for the ongoing Type 1channel access procedure is smaller than the uplink channel accesspriority class value p₂ indicated in the DCI, the wireless device mayterminate the ongoing channel access procedure.

In an example, a base station may indicate Type 2 channel accessprocedure in the DCI of an uplink grant scheduling transmission(s)including PUSCH on a channel when: the base station has transmitted onthe channel according to a channel access procedure; or base station mayindicate using the ‘UL duration and offset’ field that the wirelessdevice may perform a Type 2 channel access procedure fortransmissions(s) including PUSCH on a channel in subframe n when thebase station has transmitted on the channel according to a channelaccess procedure described; or a base station may indicate using the ‘ULduration and offset’ field and ‘COT sharing indication for AUL’ fieldthat a wireless device configured with autonomous uplink may perform aType 2 channel access procedure for autonomous uplink transmissions(s)including PUSCH on a channel in subframe n when the base station hastransmitted on the channel according to a channel access procedure andacquired the channel using the largest priority class value and the basestation transmission includes PDSCH, or a base station may scheduleuplink transmissions on a channel, that follows a transmission by thebase station on that channel with a duration of T_(short_ul)=25 us, ifthe uplink transmissions occurs within the time interval starting at t₀and ending at t₀+T_(CO), where T_(CO)=T_(m,cot,p)+T_(g), where t₀ is thetime instant when the base station has started transmission, T_(m,cot,p)value is determined by the base station, T_(g) is the total duration ofall gaps of duration greater than 25 us that occur between the DLtransmission of the base station and uplink transmissions scheduled bythe base station, and between any two uplink transmissions scheduled bythe base station starting from t₀.

In an example, the base station may schedule uplink transmissionsbetween t₀ and t₀+T_(CO) without gaps between consecutive uplinktransmissions if they can be scheduled contiguously. For an uplinktransmission on a channel that follows a transmission by the basestation on that channel within a duration of T_(short_ul)=25 us, thewireless device may use Type 2A channel access procedure for the ULtransmission.

In an example, if the base station indicates Type 2 channel accessprocedure for the wireless device in the DCI, the base station mayindicate the channel access priority class used to obtain access to thechannel in the DCI.

For indicating a Type 2 channel access procedure, if the gap is at least25 us, or 16 us, or up to 16 us, the base station may indicate Type 2A,or Type 2B, or Type 2C uplink channel procedures, respectively.

In an example, if a wireless device is scheduled to transmit on a set ofchannels C, and if Type 1 channel access procedure is indicated by theuplink scheduling grants for the uplink transmissions on the set ofchannels C, and if the uplink transmissions are scheduled to starttransmissions at the same time on all channels in the set of channels C;or if the wireless device intends to perform an autonomous uplinktransmission on configured resources on the set of channels C with Type1 channel access procedure, and if UL transmissions are configured tostart transmissions on the same time all channels in the set of channelsC; and if the channel frequencies of set of channels C is a subset ofone of the sets of channel frequencies, the wireless device may transmiton channel c_(i)∈C using Type 2 channel access procedure, if Type 2channel access procedure is performed on channel c_(i) immediatelybefore the wireless device transmission on channel c_(j)∈C, i≠j, and ifthe wireless device has accessed channel c_(j) using Type 1 channelaccess procedure, where channel c_(j) is selected by the wireless deviceuniformly randomly from the set of channels C before performing Type 1channel access procedure on any channel in the set of channels C and thewireless device may not transmit on channel c_(i)∈C within the bandwidthof a carrier, if the wireless device fails to access any of thechannels, of the carrier bandwidth, on which the wireless device isscheduled or configured by UL resources.

In an example, a wireless device may transmit the transmission usingType 1 channel access procedure after first sensing the channel to beidle during the slot durations of a defer duration T_(d); and after thecounter N is zero in step 4. The counter N may be adjusted by sensingthe channel for additional slot duration(s) according to the actionsdescribed below:

1) set N=N_(init), where N_(init) is a random number uniformlydistributed between 0 and CW_(p), and go to action 4;

2) if N>0 and the UE chooses to decrement the counter, set N=N−1;

3) sense the channel for an additional slot duration, and if theadditional slot duration is idle, go to action 4; else, go to action 5;

4) if N=0, stop; else, go to action 2.

5) sense the channel until either a busy slot is detected within anadditional defer duration T_(d) or all the slots of the additional deferduration T_(d) are detected to be idle;

6) if the channel is sensed to be idle during all the slot durations ofthe additional defer duration T_(d), go to action 4; else, go to action5;

In an example, if a wireless device has not transmitted an uplinktransmission on a channel on which uplink transmission(s) are performedafter action 4 in the process above, the wireless device may transmit atransmission on the channel, if the channel is sensed to be idle atleast in a sensing slot duration T_(sl) when the UE is ready to transmitthe transmission and if the channel has been sensed to be idle duringall the slot durations of a defer duration T_(d) immediately before thetransmission. If the channel has not been sensed to be idle in a sensingslot duration T_(sl) when the wireless device first senses the channelafter it is ready to transmit, or if the channel has not been sensed tobe idle during any of the sensing slot durations of a defer durationT_(d) immediately before the intended transmission, the wireless devicemay proceed to action 1 after sensing the channel to be idle during theslot durations of a defer duration T_(d).

The defer duration T_(d) may consist of duration T_(f)=16 us immediatelyfollowed by m_(p) consecutive slot durations where each slot duration isT_(sl)=9 us, and T_(f) includes an idle slot duration T_(sl) at start ofT_(f). CW_(min,p)≤CW_(p)≤CW_(max,p) may be the contention window.CW_(min,p) and CW_(max,p) may be chosen before step 1 of the procedureabove. m_(p), CW_(min,p), and CW_(max,p) may be based on a channelaccess priority class p as shown in FIG. 16, that is signalled to thewireless device.

In an example, if a wireless device is indicated to perform Type 2A ULchannel access procedures, the wireless device may use Type 2A ULchannel access procedure for a UL transmission. The UE may transmit thetransmission immediately after sensing the channel to be idle for atleast a sensing interval T_(short_ul)=25 us. T_(short_ul) may consist ofa duration T_(f)=16 us immediately followed by one slot durationT_(sl)=9 us and T_(f) may include an idle slot duration T_(sl) at startof T_(f). The channel may be considered to be idle for T_(short_ul) ifit is sensed to be idle during the slot durations of T_(short_ul).

In an example, if a wireless device is indicated to perform Type 2B ULchannel access procedures, the wireless device may use Type 2B ULchannel access procedure for a uplink transmission. The wireless devicemay transmit the transmission immediately after sensing the channel tobe idle.

In an example, if a wireless device is indicated to perform Type 2C ULchannel access procedures, the wireless device transmits immediatelywithout sensing the channel.

In an example embodiment, a wireless device (e.g., a MAC entity of thewireless device) may employ one or more processes to handle the uplinkLBT failures for uplink transmissions, such as uplink transmissions forone or more uplink channels (e.g., PUSCH, PUCCH and/or PRACH) and/or oneor more signals (e.g., SRS). In an example, the wireless device maydetect/determine consistent uplink LBT failures to detect/determineuplink LBT problems. A MAC entity of the wireless device may receivenotifications of uplink LBT failures from the physical layer to detectconsistent uplink LBT failures.

In an example, detection/determination of consistent uplink LBT failuresmay be based on a counter and/or timer. A value of the counter may beincremented based on detecting an uplink LBT failure. In an example, athreshold may be configured and a consistent uplink LBT failure may bedetermined based on the counter reaching the threshold. A consistentuplink LBT failure event may be triggered based on the uplink LBTfailure counter reaching the threshold value. In an example, a timer maybe started based on detecting a consistent uplink LBT failure and thevalue of the counter may be reset (e.g., reset to zero) based on anexpiry of the timer. The wireless device may receive configurationparameters indicating the threshold value for the counter (e.g., a MaxCount value) and a value of the timer. In an example, the threshold forthe counter and/or the timer value may be configured per BWP and/or percell. In an example, the threshold may be reset (e.g., reset to zero)based on the reconfiguration (e.g., in response to receiving an RRCreconfiguration message) of one or more parameters of the consistentuplink failure detection such as the threshold and/or timer value.

The wireless device may determine consistent LBT failure (e.g., for acell and/or a BWP of the cell and/or an LBT sub-band of the BWP of thecell). The wireless device may indicate the consistent LBT failure(e.g., for a cell and/or a BWP of the cell and/or an LBT sub-band of theBWP of the cell) to the base station. The cell for which the wirelessdevice may indicate consistent LBT failure may be a secondary cell or aprimary cell (e.g., PCell or PSCell). In an example, the wireless devicemay autonomously take a recovery action. In an example, the wirelessdevice may receive a command from the base station in response toindication of the consistent LBT failure to the base station. Therecovery action may include switching the BWP and/or performing a randomaccess process (e.g., in the new BWP after switching). In an example,the wireless device may stop one or more timers (e.g., BWP inactivitytimer) based on the detecting/determining the consistent LBT failure.

In an example, the determining/detecting of the consistent uplink LBTfailure on a cell/BWP may be based on a plurality of uplinktransmissions (e.g., via one or more uplink channels and/or one or moreuplink signals) on the cell/BWP. In an example, thedetermining/detecting of the consistent uplink LBT failure may beindependent of uplink transmission type. The LBT failures for differentuplink transmissions may be used to determine the consistent uplink LBTfailure regardless of the uplink transmission types (e.g., PUSCH, PUCCH,etc.). The consistent uplink LBT failure mechanism may have the samerecovery mechanism for all uplink LBT failures regardless of the uplinktransmission type.

In an example, based on detecting/determining/declaring consistentuplink LBT failures on PCell or PSCell, the wireless device may switch acurrent active BWP (of PCell or PSCell) to a second BWP (of PCell orPSCell). The wireless device may initiate a random access process in thesecond BWP based on the second BWP being configured with random accessresources. The wireless device may perform radio link failure (RLF)recovery based on the consistent uplink LBT failure being detected onthe PCell and consistent uplink LBT failure being detected on N possibleBWPs of the PCell. In an example, based on detecting/determiningconsistent uplink LBT failures on a PSCell and after detecting aconsistent uplink LBT failure on N BWPs of the PSCell, the wirelessdevice may indicate a failure to a master base station via a secondarycell group (SCG) failure information procedure. In an example, N may bethe number of configured BWPs with configured random access resources.In an example, after detecting consistent uplink LBT failure on PCell orPSCell, the wireless device may determine which BWP to switch if N islarger than one. The value of N may be configurable (e.g., via RRC) ormay be pre-determined/pre-configured.

In an example, based on detecting/determining consistent uplink LBTfailures on a cell (e.g., a SCell or PCell), the wireless device mayindicate the consistent LBT failure on the cell to the base stationbased on an LBT failure indication MAC CE. The MAC CE may reportconsistent uplink LBT failure on one or more Cells. The MAC CE formatmay support multiple entries to indicate the Cells which have alreadydeclared consistent uplink LBT failures. In an example, the LBT failureindication MAC CE may indicate/include cell index(s) where uplink LBTfailure occurs. In an example, the format of the LBT failure indicationMAC CE may be a bitmap to indicate whether corresponding serving cellhas declared consistent uplink LBT failure or not.

The LBT failure indication MAC CE may be transmitted on a differentserving cell than a SCell which has consistent UL LBT problem. In anexample, the LBT failure indication MAC CE may indicate consistentuplink LBT failures on one or more cells and the wireless device maytransmit the LBT failure indication MAC CE based on an uplink grant on acell other than the one or more cells. The MAC CE for uplink LBT failureindication may have higher priority than data but lower priority than abeam failure recovery (BFR) MAC CE.

The wireless device may trigger scheduling request if there is noavailable uplink resource for transmitting the MAC CE for a SCell uplinkLBT failure indication. The wireless device may receive configurationparameters of a SR configuration associated with uplink LBT failureindication. The configuration parameters may comprise an identifierindicating that the SR is associated with uplink LBT failure indication.In an example, when a SR configuration associated with uplink LBTfailure indication is not configured for the wireless device and noresource is available for transmitting the MAC CE for indicating SCelluplink LBT failure, the wireless device may start a random accessprocess.

In an example, when a SR for uplink LBT failure indication is triggeredand the wireless device has an overlapping SR PUCCH resource with theSCell LBT failure SR PUCCH resource, the wireless device may select theSCell LBT failure SR PUCCH resource for transmission.

In an example, the wireless device may cancel the consistent LTB failurefor a serving cell (or BWP(s)) (e.g., may not consider the cell ashaving consistent LBT failure) based on the wireless device successfullytransmitting an LBT failure MAC CE indicating the serving cell.

In an example, when consistent UL LBT failure is declared on SpCell, thewireless device may trigger MAC CE to indicate where failure happened.The MAC CE may be sent on the BWP that the wireless device switched toduring the random access process.

In an example, different LBT failures, irrespective of channel, channelaccess priority class, and LBT type, may be considered equivalent forthe consistent UL LBT failure detection procedure at a MAC entity of awireless device.

In an example, upon switching to a new BWP after detecting consistentLBT failures on a BWP of the PCell/PSCell, the wireless device mayincrement a counter (e.g., a BWP switching counter). The BWP switchingcounter may be used by the wireless device to initiate a radio linkfailure process based on the BWP switching counter reaching a value(e.g., N). The wireless device may reset the BWP switching counter whenthe random access process on a BWP of the PCell/PSCell beingsuccessfully completed.

In an example, in response to the BWP switching due to consistent uplinkLBT failure on PCell/PSCell, the wireless device may indicate theconsistent uplink LBT failure via dedicated uplink resource (e.g.PRACH). For example, the PRACH resources used for indication ofconsistent uplink LBT failure may be dedicated to consistent uplink LBTfailure indication

In an example, the uplink LBT failure information reported by the UE mayinclude one or more BWP indexes of BWPs with consistent uplink LBTfailures, one or more cell indexes of one or more cells with consistentuplink LBT failures and/or one or more measurement results (e.g.,RSRP/RSRQ/RSSI/CO) of the serving/neighbor cells

In an example, the wireless device may perform an LBT for an uplinktransmission comprising the uplink failure indication MAC CE based on ahighest priority channel access priority class (e.g., lowest numberchannel access priority).

In an example, the wireless device may reset the uplink LBT counter fora cell/BWP based on expiry of an uplink LBT timer and/or based onreceiving one or more messages indicating reconfiguration of uplink LBTconfiguration parameters for detecting consistent LBT failures and/orbased on transmitting an uplink channel or uplink signal on the cell/BWPin response to successful uplink LBT. In an example, successful uplinkLBT for the cell/BWP may indicate that the cell/BWP no longer hasconsistent LBT failures.

In an example, in response to BWP switching caused by detection ofconsistent uplink LBT failures on SpCell, a MAC entity may stop anongoing random access procedure and may initiate a new random accessprocedure.

In an example, based on switching BWP due to detecting/declaringconsistent LBT failure on a BWP of PCell or PSCell, the wireless devicemay initiate a random access process and may not perform othertransmissions (e.g., may not resume suspended configured grantstransmissions).

In an example, a wireless device may autonomously deactivate aconfigured grant for Sell(s) experiencing a consistent UL LBT failure.

In an example, based on detecting/declaring consistent uplink LBTfailure for a cell/BWP, ongoing transmissions (e.g., PUSCH transmission,SRS transmission, PUCCH transmission, RACH transmission, etc.) on activeBWP of a SCell with consistent uplink LBT failure may be suspended.

In an example, based on detecting/declaring consistent uplink LBTfailure for a cell/BWP, type 2 configured grants on the cell/BWP may becleared. In an example, based on detecting/declaring consistent uplinkLBT failure for a cell/BWP, type 1 configured grants on the cell/BWP maybe suspended. In an example, based on detecting/declaring consistentuplink LBT failure for a BWP, BWP inactivity for a downlink BWPassociated with the BWP may be stopped.

In an example, based on switching BWP due to detecting/declaringconsistent LBT failure on a BWP of PCell or PSCell, a counter fordetection of consistent uplink LBT failure of the BWP may be resetand/or a timer for consistent uplink LBT failure detection of the BWPmay be stopped.

In an example, based on an uplink transmission failure due to LBT, aphysical layer of a wireless device may send LBT failure indication to aMAC entity of the wireless device. The MAC entity of the wireless devicemay, based on receiving an LBT failure indication, start anlbt-FailureDetectionTimer and increment an LBT_COUNTER. Based on thelbt-FailureDetectionTimer expiring, the LBT_COUNTER may be reset. Basedon LBT_COUNTER reaching a configured threshold value before thelbt-FailureDetectionTimer expiring, the wireless device may trigger aconsistent uplink LBT failure event. In an example, a “failureType” inSCG failure information may indicate consistent uplink LBT failures.

In an example, the Scheduling Request (SR) may be used for requestingUL-SCH resources for new transmission. A MAC entity of a wireless devicemay be configured with zero, one, or more SR configurations. An SRconfiguration may comprise of a set of PUCCH resources for SR acrossdifferent BWPs and cells. In an example, for a logical channel, a PUCCHresource for SR may be configured per BWP.

In an example, a SR configuration may correspond to one or more logicalchannels. A logical channel may be mapped to zero or one SRconfiguration, which may be configured by RRC. The SR configuration ofthe logical channel that triggered the buffer status report (BSR) (ifsuch a configuration exists) may be considered as corresponding SRconfiguration for the triggered SR.

In an example, RRC may configure the following parameters for thescheduling request procedure: sr-ProhibitTimer (e.g., per SRconfiguration); and sr-TransMax (e.g., per SR configuration). In anexample, the following variables may be used for the scheduling requestprocedure: SR_COUNTER (e.g., per SR configuration).

In an example, if an SR is triggered and there are no other SRs pendingcorresponding to the same SR configuration, the MAC entity may set theSR_COUNTER of the corresponding SR configuration to 0.

In an example, when an SR is triggered, it may be considered as pendinguntil it is cancelled. One or more pending SR(s) triggered prior to theMAC PDU assembly may be cancelled and respective sr-ProhibitTimer may bestopped when the MAC PDU is transmitted and this PDU includes a Long orShort BSR MAC CE which contains buffer status up to (and including) thelast event that triggered a BSR prior to the MAC PDU assembly. One ormore pending SR(s) may be cancelled and respective sr-ProhibitTimer maybe stopped when the UL grant(s) can accommodate all pending dataavailable for transmission.

In an example, PUCCH resources on a BWP which is active at the time ofSR transmission occasion may be considered valid.

In an example, as long as at least one SR is pending, for each pendingSR, if the MAC entity has no valid PUCCH resource configured for thepending SR, the MAC entity may initiate a Random Access procedure on theSpCell and cancel the pending SR.

In an example, based on at least one SR is pending, for each pending SR,if the MAC entity has valid PUCCH resource configured for the pendingSR, for the SR configuration corresponding to the pending SR: when theMAC entity has an SR transmission occasion on the valid PUCCH resourcefor SR configured; and if sr-ProhibitTimer is not running at the time ofthe SR transmission occasion; and if the PUCCH resource for the SRtransmission occasion does not overlap with a measurement gap; and ifthe PUCCH resource for the SR transmission occasion does not overlapwith a UL-SCH resource: if SR_COUNTER<sr-TransMax: the wireless devicemay increment SR_COUNTER by 1; instruct the physical layer to signal theSR on one valid PUCCH resource for SR; and start the sr-ProhibitTimer.If SR_COUNTER=sr-TransMax: the wireless device may notify RRC to releasePUCCH for all Serving Cells; notify RRC to release SRS for all ServingCells; clear any configured downlink assignments and uplink grants;clear any PUSCH resources for semi-persistent CSI reporting; initiate aRandom Access procedure on the SpCell and cancel all pending SRs.

In an example, the selection of which valid PUCCH resource for SR tosignal SR on when the MAC entity has more than one overlapping validPUCCH resource for the SR transmission occasion may be based on thewireless device implementation.

In an example, if more than one individual SR triggers an instructionfrom a MAC entity to a PHY layer to signal the SR on the same validPUCCH resource, the SR_COUNTER for the relevant SR configuration may beincremented only once.

In an example, the MAC entity may stop, if any, ongoing Random Accessprocedure due to a pending SR which has no valid PUCCH resourcesconfigured, which was initiated by MAC entity prior to the MAC PDUassembly. Such a Random Access procedure may be stopped when the MAC PDUis transmitted using a UL grant other than a UL grant provided by RandomAccess Response, and this PDU includes a BSR MAC CE which containsbuffer status up to (and including) the last event that triggered a BSRprior to the MAC PDU assembly, or when the UL grant(s) can accommodateall pending data available for transmission.

In an example, a wireless device may be configured by a higher layerparameter (e.g., SchedulingRequestResourceConfig) a set ofconfigurations for SR in a PUCCH transmission for example using PUCCHformat 0 or PUCCH format 1.

The wireless device may be configured a PUCCH resource bySchedulingRequestResourceId providing a PUCCH format 0 resource or aPUCCH format 1 resource. The wireless device may also be configured aperiodicity SR_(PERIODICITY) in symbols or slots and an offsetSR_(OFFSET) in slots by periodicityAndOffset for a PUCCH transmissionconveying SR. If SR_(PERIODICITY) is larger than one slot, the UE maydetermine a SR transmission occasion in a PUCCH to be in a slot withnumber n_(s,f) ^(μ) in a frame with number n_(f) if (n_(f)·N_(slot)^(frame,μ)+n_(s,f) ^(μ)−SR_(OFFSET))mod SR_(PERIODICITY)=0.

In an example, if SR_(PERIODICITY) is one slot, the UE may expect thatSR_(OFFSET)=0 and every slot may be a SR transmission occasion in aPUCCH.

In an example, if SR_(PERIODICITY) is smaller than one slot, the UE maydetermine a SR transmission occasion in a PUCCH to start in a symbolwith index l if (l−l₀ mod SR_(PERIODICITY)) mod SR_(PERIODICITY)=0 wherel₀ may be the value of startingSymbolIndex.

In an example, if the UE determines that, for a SR transmission occasionin a PUCCH, the number of symbols available for the PUCCH transmissionin a slot is smaller than the value provided by nrofSymbols, the UE maynot transmit the PUCCH in the slot.

In an example, the IE SchedulingRequestConfig may be used to configurethe parameters, for the dedicated scheduling request (SR) resources.

In an example, the parameter schedulingRequestToAddModList may indicatea list of Scheduling Request configurations to add or modify. Theparameter schedulingRequestToReleaseList may indicate a list ofScheduling Request configurations to release. The parameterschedulingRequestId may be used to modify a SR configuration and toindicate, in LogicalChannelConfig, the SR configuration to which alogical channel is mapped and to indicate, inSchedulingRequestresourceConfig, the SR configuration for which ascheduling request resource is used. The parameter sr-ProhibitTimer mayindicate a timer for SR transmission on PUCCH. Value is in ms. Value ms1may correspond to 1 ms, value ms2 may correspond to 2 ms, and so on.When the field is absent, the UE may apply the value 0. The parametersr-TransMax may indicate maximum number of SR transmissions. Value n4may correspond to 4, value n8 may correspond to 8, and so on.

In an example, the IE SchedulingRequestId may be used to identify aScheduling Request instance in the MAC layer.

In an example, the IE SchedulingRequestResourceConfig may determinephysical layer resources on PUCCH where the UE may send the dedicatedscheduling request (D-SR). A parameter periodicityAndOffset may indicateSR periodicity and offset in number of symbols or slots. A parameterresource may indicate an ID of the PUCCH resource in which the UE maysend the scheduling request. The actual PUCCH-Resource may be configuredin PUCCH-Config of the same UL BWP and serving cell as thisSchedulingRequestResourceConfig. The network may configure aPUCCH-Resource of PUCCH-format0 or PUCCH-format1 (other formats notsupported). The schedulingRequestID may indicate an ID of theSchedulingRequestConfig that uses this scheduling request resource.

In an example, the IE SchedulingRequestResourceId may be used toidentify scheduling request resources on PUCCH.

A MAC PDU may comprise of one or more MAC subPDUs. A MAC subPDU maycomprise of one of the following: a MAC subheader only (includingpadding); a MAC subheader and a MAC SDU; a MAC subheader and a MAC CE; aMAC subheader and padding. The MAC SDUs may be of variable sizes. A MACsubheader may correspond to either a MAC SDU, a MAC CE, or padding. AMAC subheader except for fixed sized MAC CE, padding, and a MAC SDUcontaining UL CCCH may comprise of the four header fields R/F/LCID/L. AMAC subheader for fixed sized MAC CE, padding, and a MAC SDU containingUL CCCH may comprise of the two header fields R/LCID. FIG. 17A, FIG. 17Band FIG. 17C show example MAC subheaders. For example, FIG. 17A shows anexample R/F/LCID/L MAC subheader with 8-bit L field. FIG. 17B shows anexample R/F/LCID/L MAC subheader with 16-bit L field and FIG. 17C showsan example R/LCID MAC subheader. MAC CEs may be placed together. DL MACsubPDU(s) with MAC CE(s) may be placed before a MAC subPDU with MAC SDUand MAC subPDU with padding. The UL MAC subPDU(s) with MAC CE(s) may beplaced after the MAC subPDU(s) with MAC SDU and before the MAC subPDUwith padding in the MAC PDU. The size of padding may be zero.

FIG. 18 shows an example uplink MAC PDU (transport block) comprising aplurality of MAC subPDUs, wherein a MAC subPDU may comprise a subheaderand MAC SDU (e.g. data from one or more logicals) or a MAC subPDU maycomprise a subheader and a MAC control element (MAC CE). A MAC CE may bea fixed-size MAC CE wherein the length of the MAC CE may be a fixedvalue or may be a variable-sized MAC CE wherein the length of the MAC CEmaybe variable.

The subheader of a MAC subPDU may comprise a logical channel identifier(LCID). The LCID field may identify the logical channel instance of thecorresponding MAC SDU or the type of the corresponding MAC CE orpadding. In an example, a MAC subheader may comprise one LCID field. TheLCID field size may be 6 bits. One or more first LCIDs (e.g., LCIDs forMAC CEs included in MAC subPDUs) may have pre-defined values and one ormore second LCIDs (e.g., LCIDs for MAC SDUs included in subPDUs) may beconfigured for a logical channel/bearer, the data of which is includedin the MAC subPDU. For example, an RRC parameter logicalchannelidentitymay indicate an LCID of a logical channel.

When a MAC subPDU comprises a MAC SDU or a variable-sized MAC CE, thesubheader contained in the MAC subPDU may have a length field. TheLength field may indicate the length of the corresponding MAC SDU orvariable-sized MAC CE in bytes. There may be one L field per MACsubheader except for subheaders corresponding to fixed-sized MAC CEs,padding, and MAC SDUs containing UL CCCH. The size of the L field may beindicated by the F field.

The F field (Format field) may indicate the size of the Length field.There may be one F field per MAC subheader except for subheaderscorresponding to fixed-sized MAC CEs, padding, and MAC SDUs containingUL CCCH. The size of the F field may be 1 bit. The value 0 may indicate8 bits of the Length field. The value 1 may indicate 16 bits of theLength field.

In an example as shown in FIG. 19, a wireless device may determineconsistent LBT failures on a cell and/or a BWP of a cell and/or an LBTsubband of a BWP of a cell. The determination of consistent LBT failureson the cell/BWP/LBT subband may be based on counting a number of uplinkLBT failures for uplink transmissions on the cell/BWP/LBT subband. Theuplink transmission may be via an uplink channel (e.g., PUSCH, PUCCH,PRACH) or an uplink signal (e.g., SRS). For example, the wireless devicemay increment a counter based on determining/detecting an uplink LBTfailure for an uplink transmission and may declare/trigger a consistentLBT failure indication based on the counter reaching a first value. Thefirst value for the counter may be configurable (e.g., by RRC). Thewireless device may receive configuration parameters comprising a firstparameter indicating the first value. For example, a MAC entity of thewireless device may determine an LBT failure based on an indication ofthe LBT failure for the uplink transmission from the physical layer ofthe wireless device. The wireless device may start a timer based onreceiving an LBT failure indication and may reset the LBT counter (e.g.,reset to zero) based on the timer expiring. The wireless device maytransmit an LBT failures indication MAC CE based on thetriggering/declaring/determining a consistent LBT failure for a firstcell/BWP/LBT subband. The LBT failures indication MAC CE may indicateconsistent LBT failure on the first cell (and/or first BWP or first LBTsubband of the first cell) and one or more other cells/BWPs/LB subbandsthat have consistent LBT failures.

In an example as shown in FIG. 20, the wireless device maydeclare/trigger consistent LBT failures on a cell/BWP/LBT subband basedon a consistent LBT failure determination described earlier. Thewireless device may determine that no uplink resource is available fortransmission of an LBT failure indication MAC CE. Based on no uplinkresource being available for transmission of the LBT failure indicationMAC CE, the wireless device may trigger a scheduling request. Thewireless device may transmit a scheduling request signal based on ascheduling request configuration. The scheduling request configurationmay be for transmission of scheduling request signals related to uplinkLBT failure recovery. In an example, the configuration parameters of thescheduling request configuration (e.g., a scheduling request identifierand/or other parameters) may indicate that the scheduling requestconfiguration is for consistent LBT failure recovery. The schedulingrequest configuration may indicate resources comprising a first resourcefor transmission of the scheduling request signal.

The LBT failure indication MAC CE may have different formats, e.g., ashort format and a long format as shown in FIG. 21 and FIG. 22. The LBTfailure indication MAC CE may comprise of bitmaps. In an example, theshort format may comprise one octet wherein a first bit of the octet maybe a reserved bit (e.g., see FIG. 21) and each of the other seven bitsmay correspond to a cell and/or BWP of a cell and/or LBT subband of acell. In an example, a first bit of the octet may correspond to a PCelland/or PSCell (e.g., see FIG. 22) and the other seven bits of the octetmay correspond to secondary cells. A value of one for bit i of the octetmay indicate that the cell/BWP/LBT subband corresponding to the bit i ofthe octet has consistent LBT failures and a value of zero for bit i ofthe octet may indicate that cell/BWP/LBT subband corresponding to thebit i of the octet does not have consistent LBT failures.

In an example, a long format for LBT failure indication MAC CE maycomprise four octets wherein a first bit of a first octet of the fouroctets may be a reserved bit (e.g., see FIG. 21) and each of the otherthirty one bits may correspond to a cell and/or BWP of a cell and/or LBTsubband of a cell. In an example, a first bit of a first octet maycorrespond to a PCell and/or PSCell (e.g., see FIG. 22) and the otherthirty one bits of the four octet may correspond to secondary cells. Avalue of one for bit i of the four octets may indicate that thecell/BWP/LBT subband corresponding to the bit i has consistent LBTfailures and a value of zero for bit i may indicate that cell/BWP/LBTsubband corresponding to the bit i does not have consistent LBTfailures.

The format of the LBT failure indication MAC CE (e.g., long or shortformat) may be based on indexes of the serving cells that haveconsistent LBT failures. In an example, the short format may be used forLBT failure indication MAC CE based on indexes of serving cellsexperiencing consistent LBT failures being smaller than a first value(e.g., eight). In an example, the long format may be used for LBTfailure indication MAC CE based on indexes of serving cells experiencingconsistent LBT failures being larger than or equal to a second value(e.g., eight).

A wireless device may be configured with a plurality of unlicensedcells. One or more of the plurality of unlicensed cells mayexperience/have consistent LBT failures triggering LBT failureindication. The wireless device may trigger a scheduling request basedon triggering LBT failure indication and no uplink resource beingavailable for transmission of an LBT failure indication MAC CE. Based onexisting solutions and as shown in FIG. 23, transmission of thescheduling request signals by the wireless device may result inreceiving uplink grants on the cells that experience consistent LBTfailures which may be not be useful for transmission of LBT failureindication. Existing solutions for consistent LBT failure recovery maynot be efficient leading to a slow recovery from consistent LBTfailures. There is a need to enhance the existing uplink LBT failurerecovery mechanisms to improve the speed of recovery from consistent LBTfailures. Example embodiments enhance the recovery form consistentuplink LBT failures on unlicensed cells.

In an example embodiment, a wireless device may receive one or moremessages comprising configuration parameters. The one or more messagesmay comprise one or more RRC messages. The one or more messages maycomprise first configuration parameters of a plurality of cells. In anexample, the plurality of cells may comprise a plurality of secondarycells. In an example, the plurality of cells may comprise a primary celland one or more secondary cells. In an example, the plurality of cellsmay comprise a plurality of cell groups comprising a primary cell groupprovided to the wireless device by a master base station and a secondarycell group provided to the wireless device by a secondary base station,wherein the primary cell group may comprise a primary cell (PCell) andthe secondary cell group may comprise a primary secondary cell (PSCell).In an example, the plurality of cells may comprise a secondary cell withuplink control channel (e.g., PUCCH SCell), wherein the secondary cellwith uplink control channel carries uplink control informationassociated with a first plurality of cells (e.g., secondary PUCCH group)of the plurality of cells and the primary cell carries uplink controlinformation associated with a second plurality of cells (e.g., a primaryPUCCH group) of the plurality of cells.

The one or more messages may further comprise second configurationparameters of a scheduling request configuration. The scheduling requestconfiguration may indicate a plurality of resources for transmission ofscheduling request signals. The scheduling request configuration mayindicate physical uplink control channel (PUCCH) resources fortransmission of scheduling request signals. The PUCCH resources may beconfigured on a primary cell or a secondary cell configured with PUCCHresources (e.g., PSCell or PUCCH SCell). In an example, the secondconfiguration parameters may comprise an identifier of the schedulingrequest configuration. In an example, the second configurationparameters may comprise one or more parameters indicating radioresources for transmission of the scheduling request signals. The one ormore parameters may comprise a periodicity and offset parameterindicating the SR periodicity (e.g., in number of symbols or slots) anda resource parameter indicating an identifier of the PUCCH resource inwhich the wireless device may transmit the scheduling request signal.

The scheduling request configuration may be an uplink failure recoveryscheduling configuration. In an example, the second configurationparameters of the uplink LBT failure recovery scheduling requestconfiguration may comprise an identifier indicating that the schedulingrequest configuration is for uplink LBT failure recovery. The schedulingrequest configuration may indicate physical uplink control channel(PUCCH) resources for transmission of scheduling request signals forrecovery from consistent LBT failures. The scheduling requestconfiguration may be for recovery from consistent LBT failures, whereinthe wireless device may transmit one or more scheduling request signalsbased the second configuration parameters for recovery from consistentLBT failures.

The wireless device may determine, as shown in FIG. 24-FIG. 29,consistent uplink LBT failures on one or more cells/BWPs/LBT sub-bandsof the plurality of cells/BWPs/LBT sub-bands. The wireless device maydetermine/declare/trigger the consistent LBT failures on the one or morecells of the plurality of cells based on LBT failure indicationsreceived from the physical layer of the wireless device to a MAC entityof the wireless device and based on a consistent LBT failuredetermination process. The consistent LBT failure determination processmay be based on one or more counters (e.g., LBT counter) and one or moretimers. The wireless device may trigger an LBT failure indication MAC CEbased on a determination of the consistent LBT failures on acell/BWP/LBT sub-band.

The determination of consistent LBT failures on a cell/BWP/LBT sub-bandmay be based on notifications of LBT failures from physical layer of thewireless device to a MAC entity of the wireless device and based on aprocess that employs one or more counters (e.g., counting number of LBTfailures) and one or more timers. For example, the determination ofconsistent LBT failures on a cell/BWP may be based on an LBT counterassociated with the cell/BWP/LBT sub-band reaching a threshold value.The LBT counter may be incremented based on receiving a notification ofLBT failure for an uplink transmission (e.g., for an uplink channel oruplink signal) from the physical layer. The one or more messages maycomprise a parameter indicating the threshold value for the LBT counter.The wireless device may start a timer based on receiving a notificationof LBT counter from the physical layer. The wireless device may startthe timer with a value, wherein the value is configurable (e.g., byRRC). The wireless device may receive configuration parametersindicating the timer value. The wireless device may reset the LBTcounter based on the timer expiring.

Based on the consistent LBT failures on the one or more cells of theplurality of cells, the wireless device may transmit a schedulingrequest signal. The wireless device may transmit the scheduling requestsignal based on the consistent LBT failures on the one or more cells andbased on uplink resources not being available for an LBT failureindication MAC CE indicating the consistent LBT failures on the one ormore cells.

In an example embodiment as shown in FIG. 24, based on the consistentuplink LBT failures on the one or more cells, the wireless device maytransmit the scheduling request signal via a first resource of theplurality of resources indicated by the scheduling requestconfiguration. The transmitting the scheduling request may be based onan uplink control channel (e.g., PUCCH) on a primary cell or a secondarycell configured with uplink control channel (e.g., PCell or PSCell). Inan example embodiment, the first resource may indicate a request for anuplink grant on one or more first cells of the plurality of cells. In anexample, the first resource may have a first position in a firstplurality of resources of the plurality of resources. For example, thefirst resource may be the earliest resource in every K consecutiveresource. The base station may receive the scheduling request signal viathe first resource and may determine the one or more first cells of theplurality of cells based on receiving the scheduling request signal viathe first resource.

The wireless device may receive an uplink grant for a first cell of theone or more first cells based on the transmitting the scheduling requestsignal via the first resource of the plurality of resources. Thewireless device may transmit an uplink LBT failure indication MAC CEbased on the uplink grant, wherein the uplink failure indication MAC CEmay indicate the consistent uplink LBT failures on the one or morecells/BWPs/LBT subbands.

In an example embodiment as shown in FIG. 25, based on the consistentuplink LBT failures on the one or more cells/BWPs/LBT subbands, thewireless device may transmit the scheduling request signal based on thesecond configuration parameters of the uplink LBT failure recoveryscheduling request configuration, wherein the transmitting thescheduling request signal based on the second configuration parametersmay indicate one or more first cells of the plurality of cells. The basestation may receive the scheduling request signal via a resourceassociated with the second configuration parameters of the uplink LBTfailure recovery scheduling request configuration and may determine theone or more first cells of the plurality of cells based on receiving thescheduling request signal via the resource associated with the secondconfiguration parameter.

The wireless device may receive an uplink grant for a first cell of theone or more first cells based on the transmitting the scheduling requestsignal via the resource associated with the second configurationparameters of the uplink LBT failure recovery scheduling requestconfiguration.

In an example, the size of the uplink grant may be based on thescheduling request being based on the transmitted scheduling requestbeing based on the uplink LBT failure recovery scheduling requestconfiguration. For example, the size of the uplink grant may be equal toor larger than a size of an uplink LBT failures indication MAC CE of afirst format. The first format may be, for example, a long format. In anexample, the wireless device may transmit a second scheduling requestwherein the second scheduling request is associated with a schedulingrequest configuration that is not associated with recovery fromconsistent uplink LBT failures. The wireless device may receive a seconduplink grant based on transmitting the second scheduling request whereinthe size of the second uplink grant may or may not be larger than a sizeof an uplink LBT failures indication MAC CE of a first format and/or thesize of the second uplink grant may be larger than or equal to a size ofa buffer status report MAC CE.

The wireless device may transmit an uplink LBT failure indication MAC CEbased on the uplink grant, wherein the uplink failure indication MAC CEmay indicate the consistent uplink LBT failures on the one or morecells. In an example, the wireless device may transmit a transport blockbased on the uplink grant, wherein the transport block comprises theuplink LBT failure indication MAC CE. In an example, a subheaderassociated with the uplink LBT failure indication MAC CE may comprise anLCID indicating the uplink LBT failure indication MAC CE. In an example,the LCID may be one of the first LCID or the second LCID based on theuplink LBT failure indication having a short format or a long format.

In an example, the LBT failure indication MAC CE may indicate theconsistent LBT failures on one or more second cells comprising the oneor more cells. The one or more second cells may comprise the one or morecells and one or more other cells for which the consistent LBT failureis triggered after starting the scheduling request process (e.g., aftertransmitting a first scheduling request signal of one or more schedulingrequest signals of a scheduling request process for LBT failurerecovery). In an example, the LBT failure indication MAC CE may indicateconsistent LBT failures of one or more bandwidth parts of the one ormore second cells. In an example, the LBT failure indication MAC CE mayindicate consistent LBT failures of one or more sub-bands of the one ormore bandwidth parts of the one or more second cells.

In an example embodiment as shown in FIG. 26 and FIG. 27, the or morefirst cells (e.g., indicated by the scheduling request resource orscheduling request configuration used for transmission of the schedulingrequest signal) may comprise the cell on which the scheduling requestsignal is transmitted. For example, the base station may determine thatthe cell on which the scheduling request is transmitted may not be amongthe cells that have consistent uplink LBT failures.

In an example, the first cell on which the uplink grant is received, inresponse to the transmission of the scheduling request, may be the cellon which the scheduling request signal is transmitted. The base stationmay determine that the cell on which the wireless device transmits thescheduling request may not be among the cells that have consistentuplink LBT failures and may transmit the uplink grant to the wirelessdevice for the cell on which the wireless device transmits thescheduling request signal.

In an example, the first cell on which the uplink grant is received, inresponse to the transmission of the scheduling request, may bedetermined based on the cell that the scheduling request signal istransmitted. In an example, the cell on which the scheduling request istransmitted may be associated with a cell that the uplink grant istransmitted. In an example, the association between the cell on whichthe scheduling request is transmitted and the cell on which an uplinkgrant is expected may be configurable (e.g., by RRC). The wirelessdevice may receive configuration parameters indicating the associationbetween the cell on which the scheduling request is transmitted and thecell on which the uplink grant is expected/received.

In an example, the one or more first cells or the first cell of the oneor more first cells for which the uplink grant is received may not beamong the one or more cells with consistent uplink LBT failures (e.g.,may not have consistent uplink failures).

In an example embodiment as shown in FIG. 29, the one or more firstcells may comprise one or more licensed cells. The one or more firstcells may comprise one or more licensed cells based on the plurality ofcells configured for the wireless device comprising at least onelicensed cell. The first cell of the one or more first cells on whichthe uplink grant is received may be a licensed cell. In an example, thelicensed cell may be a primary cell or a primary secondary cell. In anexample, the licensed cell may be a secondary cell.

In an example embodiment as shown in FIG. 28, the one or more firstcells may comprise a primary cell or a primary secondary cell. The firstcell of the one or more first cells on which the uplink grant isreceived may be the primary cell or the primary secondary cell.

In an example, the second configuration parameters of scheduling requestfor consistent uplink LBT recovery may be a multi-bit scheduling requestwherein a scheduling request signal indicates a plurality of bits. Theplurality of bits may indicate the one or more first cells that thewireless device may expect to receive the uplink grant.

In an example embodiment as shown in FIG. 30, the scheduling requestconfiguration parameters may indicate a plurality of resources. Thewireless device may transmit a scheduling request signal via a firstresource of the plurality of resources, wherein the first resource mayindicate request for an uplink grant on a cell of the one or more firstcells of the plurality of cells. The base station may receive thescheduling request via the first resource and may determine the one ormore first cells of the plurality of cells based on the transmittedscheduling request being via the first resource. Based on thetransmitting the scheduling request being via the first resource, thewireless device may receive an uplink grant for a first cell of the oneor more first cells. The wireless device may perform a transmission(e.g., transmit one or more transport blocks) based on the uplink grant.

In an example embodiment as shown in FIG. 31, the wireless device mayreceive first configuration parameters of a first scheduling requestconfiguration in one or more scheduling request configurations. Thewireless device may transmit a scheduling request signal based on thefirst configuration parameters of the first scheduling requestconfiguration. The transmitting the scheduling request signal based onthe first configuration parameters may indicate one or more first cellsof the plurality of cells. The transmitting the scheduling requestsignal based on the first configuration parameters may indicate requestfor an uplink grant for one or more first cells of the plurality ofcells. The base station may determine the one or more first cells of theplurality of cells based on the transmitted scheduling request beingbased on the first configuration parameters. Based on the transmittedscheduling request being based on the first configuration parameters ofthe first scheduling request configuration, the wireless device mayreceive an uplink grant for a first cell of the one or more first cellsof the plurality of cells. The wireless device may perform atransmission (e.g., transmit one or more transport blocks) based on theuplink grant.

In an example embodiment as shown in FIG. 32, a wireless device maydetermine one or more consistent LBT failures on one or more cells. Thewireless device may determine that no uplink resource is available fortransmission of an LBT failure indication MAC CE to indicate the one ormore consistent LBT failures on the one or more cells and/or one or moreconsistent LBT failures on one or more bandwidth parts of the one ormore cells and/or one or more consistent LBT failures on one or more LBTsubbands of the one or more bandwidth parts of the one or more cells.Based on the one or more cells comprising a PCell and/or PSCell or theone or more cells not comprising the PCell and/or PSCell, the wirelessdevice may trigger or not trigger a scheduling request.

The wireless device may trigger a scheduling request based on thedetermination of consistent LBT failures on the one or more cells, thedetermination of no uplink resource for transmission of an LBT failureindication MAC CE and determination that the one or more cells do notcomprise a PCell and/or PSCell (e.g., the one or more cells onlycomprising secondary cells). The wireless device may transmit ascheduling request signal via a scheduling request resource. Thewireless device may receive configuration parameters of schedulingrequest indicating a plurality of scheduling request resourcescomprising the scheduling request resource. Based on the transmission ofthe scheduling request signal, the wireless device may receive an uplinkgrant indicating uplink resources. The wireless device may transmit theLBT failure indication MAC CE based on the uplink resources indicated bythe uplink grant.

Based on the determination that the one or more cells with consistentuplink LBT failure comprising a PCell and/or a PSCell (e.g., a PCelland/or PSCell and one or more secondary cells), the wireless device maynot trigger a scheduling request. The wireless device may switch from afirst BWP of the PCell/PSCell to a second BWP of the PCell/PSCell, as anactive BWP, based on determining consistent LBT failures on thePCell/PSCell. The wireless device may start a random access process onthe second BWP of the PCell/PSCell after switching to the second BWP. Inan example, the random access in the second BWP may be a four-steprandom access. In an example, the random access in the second BWP may bea two-step random access process.

In an example and with a four-step random access process in the secondBWP, the wireless device may transmit a random access preamble and mayreceive a random access response (RAR) comprising an uplink grantindicating uplink resources. The wireless device may transmit the LBTfailures indication MAC CE indicating the consistent uplink LBT failureson the one or more cells based on the uplink resources indicated by theuplink grant of the RAR. In an example, the wireless device may transmita transport block comprising the LBT failure indication MAC CE. In anexample, the wireless device may transmit the LBT failure indication MACCE based on Msg3 of the random access process. In an example and for atwo-step random access process, the wireless device may transmit the LBTfailure indication MAC CE based on MsgA.

In an example embodiment, a wireless device may receive one or moremessages, from a base station, comprising: first configurationparameters of a plurality of cells; and second configuration parametersof an uplink LBT failure recovery scheduling request configurationindicating a plurality of resources. Based on consistent uplink LBTfailures on one or more cells of the plurality of cells, the wirelessdevice may transmit a scheduling request via a first resource of theplurality of resources, wherein the first resource indicates request foran uplink grant on one or more first cells of the plurality of cells.The base station may determine the one or more first cells based on thefirst resource used for transmission of the scheduling request. Thewireless device may receive, based on the transmitting the schedulingrequest, an uplink grant for a first cell of the one or more firstcells. The wireless device may transmit an uplink LBT failuresindication MAC CE, based on the uplink grant, indicating the consistentuplink LBT failures on the one or more cells.

In an example embodiment, a wireless device may receive one or moremessages, from a base station, comprising: first configurationparameters of a plurality of cells; and second configuration parametersof an uplink LBT failure recovery scheduling request configuration.Based on consistent uplink LBT failures on one or more cells ofplurality of cells, transmitting a scheduling request based on thesecond configuration parameters, wherein the transmitted schedulingrequest being based on the second configuration parameters indicates oneor more first cells. The base station may determine the one or morefirst cells based on the transmitted scheduling request being based onthe second configuration parameters. The wireless device may receive,based on the transmitted scheduling request being based on the secondconfiguration parameters, an uplink grant for a first cell of the one ormore first cells of the plurality of cells. The wireless device maytransmit an uplink LBT failures indication MAC CE, based on the uplinkgrant, indicating the consistent uplink LBT failures on the one or morecells.

In an example, the one or more first cells may comprise the cell onwhich the scheduling request is transmitted. In an example, the firstcell, for which the wireless device receives the uplink grant, may bethe cell on which the scheduling request is transmitted. The cell onwhich the scheduling request is transmitted may be a primary cell or asecondary cell configured with uplink control channel. In an example,the cell on which the scheduling request is transmitted indicates theone or more first cells. In an example, the transmitting the schedulingrequest may be via an uplink control channel.

In an example, the one or more first cells may not be among the one ormore cells with consistent LBT failures. In an example, the one or morefirst cells may not have consistent uplink LBT failures.

In an example, the one or more first cells may comprise at least onelicensed cell. In an example, the plurality of cells may comprise one ormore licensed cells and the one or more first cells may comprise atleast one licensed cell.

In an example, the one or more first cells may comprise a primary cell(PCell) or a primary secondary cell (PSCell). In an example, the firstcell of the one or more first cells may be a PCell or a PSCell.

In an example, the wireless device may further determine/declare/triggerthe consistent LBT failures on the one or more cells of the plurality ofcells. In an example, the determining the consistent LBT failures maycomprise counting a number of uplink LBT failures; and the numberreaching a first threshold. In an example, the one or more messagescomprises a parameter indicating the first threshold. In an example, thedetermining the consistent LBT failures may comprise starting a timerbased on an indication of uplink LBT failure (e.g., from the physicallayer) and resetting a counter based on the timer expiring.

In an example, the transmitting the scheduling request may be furtherbased on an uplink resource not being available for transmission of anLBT failure indication MAC CE. In an example, uplink resources indicatedby uplink grants for the one or more cells may not available resources.

In an example, the LBT failure indication MAC CE may indicate consistentLBT failure on one or more second cells comprising the one or morecells. In an example, the LBT failure indication MAC CE may indicateconsistent LBT failure on one or more bandwidth parts of the one or moresecond cells. In an example, the LBT failure indication MAC CE mayindicate consistent LBT failure on one or more sub-bands of the one ormore bandwidth parts of the one or more second cells.

In an example, the second configuration parameters of the uplink LBTfailure recovery scheduling request configuration may comprise anidentifier indicating that the scheduling request configuration is foruplink LBT failure recovery.

In an example, the second configuration parameters of the uplink LBTfailure recovery scheduling request configuration may comprise one ormore parameters indicating radio resources for transmission of thescheduling request signals. In an example, the one or more parametersmay comprise a periodicity and offset parameter, a resource parameterindicating an identifier of the PUCCH resource in which the wirelessdevice may send the scheduling request, a scheduling resource identifierindicating an identifier of the scheduling request configuration.

In an example, the first resource used for transmission of thescheduling request may indicate one or more first cells based on aposition of the first SR resource in a plurality of SR resources.

In an example, the plurality of cells comprise a plurality of secondarycells. In an example, the plurality of cells may comprise a primary celland one or more secondary cells. In an example, the uplink grant mayindicate uplink resources for transmission of a transport blockcomprising the uplink LBT failures indication MAC CE. In an example, asubheader associated with the uplink LBT failures indication MAC CE maycomprise a logical channel identifier (LCID) indicating the uplink LBTfailures indication MAC CE. In an example, the LCID may be a first LCIDor a second LCID based on the uplink LBT failures indication MAC CEhaving a short format or a long format.

In an example, the transmitting the scheduling request may be based onan uplink control channel on a primary cell or a secondary cellconfigured with uplink control channel.

In an example, a size of the uplink grant may be based on thetransmitted scheduling request being based on the uplink LBT failurerecovery scheduling request configuration. In an example, the size ofthe uplink grant may be equal to or larger than a size of an uplink LBTfailures indication MAC CE of a first format. In an example, the firstformat may be a long format.

In an example, the scheduling request may be a multi-bit SR indicating aplurality of bits, the plurality of bits indicating the one or morefirst cells.

In an example embodiment, a wireless device may receive one or moremessages from a base station comprising: configuration parameters of aplurality of cells; and scheduling request configuration parametersindicating a plurality of resources. The wireless device may transmit ascheduling request via a first resource of the plurality of resources,wherein the first resource may indicate a request for an uplink grant ona cell of one or more first cells of the plurality of cells. The basestation may determine one or more first cells of the plurality of cellsbased on transmitted scheduling resource being via the first resource.The wireless device may receive, based on the transmitting thescheduling request via the first resource, an uplink grant for a firstcell of the one or more first cells. The wireless device may transmit atransport block based on the uplink grant.

In an example embodiment, a wireless device may receive one or moremessages from a base station comprising: configuration parameters of aplurality of cells; and first configuration parameters of a firstscheduling request configuration in one or more scheduling requestconfigurations. The wireless device may transmit a scheduling requestbased on the first configuration parameters, wherein the firstscheduling request configuration indicates one or more first cells ofthe plurality of cells. The base station may determine one or more firstcells of the plurality of cells based on the transmitted schedulingrequest being based on the first configuration parameters. The wirelessdevice may receive, based on the transmitted scheduling request beingbased on the first configuration parameters, an uplink grant for a firstcell of one or more first cells of the plurality of cells. The wirelessdevice may transmit a transport block based on uplink grant.

In an example, a wireless device may transmit, based on consistent LBTfailures on one or more cell, a scheduling request. The wireless devicemay receive an uplink grant for transmission of a transport block. Thewireless device may cancel a trigger for the scheduling request based onthe transport block comprising a MAC CE indicating the consistent LBTfailures on the one or more cells, otherwise, the wireless device maynot cancel the trigger.

In an example embodiment, a wireless device may determine consistent LBTfailures on one or more cells. The wireless device may determine that nouplink resources are available for transmission of a LBT failureindication MAC CE indicating the consistent LBT failures. The wirelessdevice may trigger a scheduling request based on whether the one or morecells comprising a primary cell or not.

In an example embodiment as shown in FIG. 33, a wireless device mayreceive, from one or more base stations, configuration parameterscomprising first configuration parameters and second configurationparameters. The wireless device may receive one or more messages (e.g.,one or more RRC messages) comprising the configuration parameters.

The first configuration parameters may be for LBT failure recovery. Inan example, the LBT failure recovery configuration parameters may bebandwidth part (BWP) specific and may be separately configured fordifferent BWPs. In an example, the configuration parameters of a BWP(e.g., a BWP of a cell in unlicensed or shared spectrum) may compriseassociated LBT failure recovery configuration parameters. In an example,the first configuration parameters may comprise a first parameterindicating a first number of LBT failure instances (e.g., a maximumcount value of LBT failure instances). The first number may be athreshold for an LBT counter and may be used for determining consistentLBT failure for a BWP. The wireless device may determine after how manyconsistent uplink LBT failure events the UE triggers uplink LBT failurerecovery for a cell (e.g., for the active BWP of the cell). An LBTcounter variable may be defined for a cell (e.g., an active BWP of thecell) and the wireless device may increment the LBT counter by based onan LBT failure of an LBT procedure performed for an uplink transmission(e.g., based on receiving a notification of an LBT failure from lowerlayers) on the cell (e.g., on the active BWP of the cell). The wirelessdevice may trigger a consistent LBT failure for a cell based on an LBTcounter, associated with the cell, reaching the first number. The firstconfiguration parameters may further comprise a second parameterindicating a value of an LBT failure detection timer. The wirelessdevice may use the LBT failure detection timer for consistent uplink LBTfailure detection for a cell (e.g., for the active BWP of the cell). Thewireless device may start/restart the LBT failure detection timer of acell (e.g., of the active BWP of the cell), with the configured value,based on an LBT failure of an LBT procedure performed for an uplinktransmission (e.g., based on receiving a notification of an LBT failurefrom lower layers). The wireless device may reset the LBT counter basedon the LBT failure detection timer expiring. In an example, the wirelessdevice may reset the LBT counter in response to receiving an RRCreconfiguration message indicating reconfiguration of the LBT failurerecovery configuration parameters.

The second configuration parameters may be for a scheduling requestconfiguration. The second configuration parameters may comprise ascheduling request identifier of the scheduling request configuration.The configuration parameters may indicate that the scheduling request IDassociated with the scheduling request is for LBT failure recovery. Inan example, the wireless device may be configured with a plurality ofscheduling request configurations and the configuration parameters mayindicate the identifier of the scheduling request configuration, in theplurality of scheduling request configurations, that may be used by thewireless device for LBT failure recovery.

The wireless device may trigger consistent LBT failures for one or morefirst serving cells (e.g., one or more first serving cells of aplurality of serving cells configured for the wireless device). Thewireless device may trigger the consistent LBT failures for the one ormore first serving cells (e.g., active bandwidth parts of the one ormore serving cells) based on the first configuration parameters. Thewireless device may trigger the consistent LBT failures for the one ormore first serving cells based on an LBT detection procedure. Forexample, an LBT counter may be defined for each cell (e.g., for anactive bandwidth part of each cell) in the one or more first servingcells and the wireless device may trigger/determine consistent LBTfailure for the cell based on the LBT counter for the cell (e.g., forthe active bandwidth part of the cell) reaching a threshold (e.g.,maximum count of LBT failure instances) configured for the cell (e.g.,for active bandwidth part of the cell).

The wireless device my determine that that no uplink resources, on oneor more second serving cells for which consistent LBT failure is nottriggered, are available for transmission of an LBT failure MAC CE. Thewireless device may determine that no uplink resources, on one or moresecond serving cells for which consistent LBT failure is not triggered,are available that may accommodate an LBT failure MAC CE plus itssubheader as a result of a logical channel prioritization procedure. Thewireless device may trigger a scheduling request based on thedetermination. The wireless device may transmit a scheduling request viaa scheduling request resource. The transmission of the schedulingrequest and the determination of the scheduling request resource may bebased on the scheduling request configuration configured for LBT failurerecovery and using the second configuration parameters. At least one ofthe scheduling request configuration and the scheduling request resourcemay indicate one or more third serving cells comprising a third servingcell. The one or more third serving cells may be the serving cells thatthe wireless device expects to receive an uplink grant. In an example,the one or more third serving cells may be the serving cells that thewireless device expects to receive an uplink grant in response todetermination of consistent LBT failure and transmission of thescheduling request for consistent LBT failure. For example, the one ormore third serving cells may comprise a cell (e.g., the schedulingrequest resource) via which the scheduling request is transmitted. Forexample, the one or more third serving cells may be determined based onthe cell used for transmission of the scheduling request (e.g., thescheduling request that indicates the consistent LBT failure). In anexample, the one or more third serving cells may comprise licensed cells(e.g., cells in the licensed spectrum). In an example, the one or morethird serving cells may comprise a PCell or a PSCell.

In response to the transmission of the scheduling request via thescheduling request resource that is associated with the schedulingrequest configuration configured for LBT failure recovery, the basestation may determine the one or more third serving cells based on atleast one of the scheduling request resource and the scheduling requestconfiguration. In an example, the one or more third serving cells maynot have consistent LBT failure and/or consistent LBT failure may not betriggered for the one or more third serving cells. The wireless devicemay receive an uplink grant for the third serving cell in the one ormore third serving cells. The uplink grant may comprise transmissionparameters of a TB. The wireless device may multiplex the LBT failureMAC CE in the TB and may transmit the TB based on the transmissionparameters indicated by the uplink grant.

The LBT failure MAC CE may have one of a short format (e.g., one octet)and a long format (e.g., four octets) wherein the format used for theLBT failure MAC CE may be based on a number of serving cells configuredfor the wireless device. For example, if the number of serving cellsconfigured for the wireless device is less than or equal to eight, theshort LBT Failure MAC CE format may be used and if the number of servingcells configured for the wireless device is more than eight, a longformat MAC CE may be used. The logical channel identifier (LCID) for theshort format LBT failure MAC CE may be a first LCID and the LCID for thelong format LBT failure MAC CE may be a second LCID. The LBT failure MACCE may comprise a plurality of bits and each bit may be associated witha serving cell. A first value (e.g., one) of the bit may indicate thatconsistent LBT failure is triggered for the corresponding serving cell.A second value (e.g., zero) of the bit may indicate that consistent LBTfailure is not triggered for the corresponding serving cell.

In an example embodiment as shown in FIG. 34, a wireless device mayreceive one or more messages (e.g., RRC messages) comprising firstconfiguration parameters of a plurality of cells and secondconfiguration parameters of a scheduling request configuration. Thewireless device may transmit a scheduling request via a radio resourcethat is associated with the scheduling request configuration. The radioresource may be on a serving cell that is configured with uplink controlchannel (e.g., a PCell/PSCell or a PUCCH SCell). At least one of thescheduling request configuration and the scheduling request resource mayindicate one or more cells that the wireless device expects to receivean uplink grant. The base station may determine the one or more cells,that the wireless device expects to receive an uplink grant, based on atleast the scheduling request resource and the scheduling requestconfiguration. The wireless device may receive an uplink grant from thebase station on a cell of the one or more cells. The uplink grant maycomprise transmission parameters for transmission of a TB. The wirelessdevice may transmit the TB based on the transmission parametersindicated by the uplink grant.

In an example embodiment as shown in FIG. 35, a wireless device maytrigger consistent LBT failures for one or more first serving cells(e.g., one or more active bandwidth parts of one or more first servingcells of a plurality of serving cells configured for the wirelessdevice). The wireless device may trigger the consistent LBT failures forthe one or more first serving cells based on an LBT detection procedure.For example, an LBT counter may be defined for each cell (e.g., for anactive bandwidth part of each cell) in the one or more first servingcells and the wireless device may trigger/determine consistent LBTfailure for the cell based on the LBT counter for the cell (e.g., forthe active bandwidth part of the cell) reaching a threshold (e.g.,maximum count of LBT failure instances) configured for the cell (e.g.,for active bandwidth part of the cell). The wireless device my determinethat that no uplink resources, on one or more second serving cells forwhich consistent LBT failure is not triggered, are available fortransmission of an LBT failure MAC CE. The wireless device may determinethat no uplink resources, on one or more second serving cells for whichconsistent LBT failure is not triggered, are available that mayaccommodate an LBT failure MAC CE plus its subheader as a result of alogical channel prioritization procedure. The wireless device maytrigger a scheduling request based on the determination. The wirelessdevice may transmit a scheduling request based on the one or more firstserving cells, for which consistent LBT failure is triggered, notcomprising a PCell/PSCell. The wireless device may receive an uplinkgrant and may transmit an LBT failure MAC CE based on the uplink grant.In an example, if the one or more first serving cells, for whichconsistent LBT failure is triggered, comprise the PCell/PSCell, thewireless device may not trigger/transmit the scheduling request and maytransmit the LBT failure MAC CE based on an uplink grant received (e.g.,included in a RAR message) based on a random access process (e.g.,random access process initiated in response to triggering consistent LBTfailure for PCell/PSCell) on the PCell/PSCell.

In an example embodiment as shown in FIG. 36, the wireless device maytrigger consistent LBT failures for a secondary cell (e.g., an activebandwidth parts of the secondary of a plurality of serving cellsconfigured for the wireless device). The wireless device may trigger theconsistent LBT failures for the secondary cell based on an LBT detectionprocedure. For example, an LBT counter may be defined for the secondarycell (e.g., for an active bandwidth part of the secondary cell) and thewireless device may trigger/determine consistent LBT failure for thesecondary cell based on the LBT counter for the secondary cell (e.g.,for the active bandwidth part of the secondary cell) reaching athreshold (e.g., maximum count of LBT failure instances) configured forthe secondary cell (e.g., for active bandwidth part of the secondarycell). The wireless device my determine that that no uplink resources,on one or more second serving cells for which consistent LBT failure isnot triggered, are available for transmission of an LBT failure MAC CE.The wireless device may determine that no uplink resources, on one ormore serving cells for which consistent LBT failure is not triggered,are available that may accommodate an LBT failure MAC CE plus itssubheader as a result of a logical channel prioritization procedure. Thewireless device may trigger a scheduling request based on thedetermination. The wireless device may transmit a scheduling requestbased on a random access process, for LBT failure recovery, not ongoingon a PCell/PSCell. The wireless device may receive an uplink grant inresponse to transmission of scheduling request and may transmit an LBTfailure recovery MAC CE based on the uplink grant. In an example, if arandom access process is ongoing on the PCell/PSCell, the wirelessdevice may not trigger/transmit the scheduling request and may transmitthe LBT failure MAC CE based on an uplink grant received based on therandom access process (e.g., included in the RAR received based on therandom access process).

In an example embodiment as shown in FIG. 37, a wireless device maytrigger consistent LBT failures for one or more serving cells (e.g., oneor more active bandwidth parts of one or more serving cells of aplurality of serving cells configured for the wireless device). Thewireless device may trigger the consistent LBT failures for the one ormore serving cells based on an LBT detection procedure. For example, anLBT counter may be defined for each cell (e.g., for an active bandwidthpart of each cell) in the one or more serving cells and the wirelessdevice may trigger/determine consistent LBT failure for the cell basedon the LBT counter for the cell (e.g., for the active bandwidth part ofthe cell) reaching a threshold (e.g., maximum count of LBT failureinstances) configured for the cell (e.g., for active bandwidth part ofthe cell). The wireless device may transmit an LBT failure MAC CE. TheLBT failure MAC CE may be one of a short format (e.g., one octet) or ofa long format (e.g., four octets). The wireless device may receive anuplink grant comprising transmission parameters for transmission of a TBand may multiplex the LBT failure MAC CE in the TB and using a logicalchannel prioritization procedure. The LBT failure MAC CE may comprise aplurality of bits. The plurality of bits may comprise a first bit and asecond plurality of bits. The plurality of bits may be associated with aplurality of indexes. Each bit in the plurality of bits may beassociated with a corresponding index. The first bit may be associatedwith a lowest index in the plurality of indexes (e.g., index 0) and maycorrespond to a primary cell (PCell or PSCell). The second plurality ofbits may correspond to a second plurality of secondary cells and eachbit in the second plurality of bits may be associated with acorresponding index. A first value (e.g., one) of a bit (e.g., the firstbit or the second plurality of bits) in the plurality of bits mayindicate that consistent LBT failure is triggered for a serving cellcorresponding to the bit. A second value (e.g., zero) of a bit (e.g.,the first bit or the second plurality of bits) in the plurality of bitsmay indicate that consistent LBT failure is not triggered for a servingcell corresponding to the bit. In an example, the wireless device mayreceive a DCI indicating switching an active bandwidth part of a cell,in the one or more cells, from a first bandwidth part (for which consistLBT failure is triggered) of the cell to a second bandwidth part of thecell.

In accordance with various exemplary embodiments in the presentdisclosure, a device (e.g., a wireless device, a base station and/oralike) may include one or more processors and may include memory thatmay store instructions. The instructions, when executed by the one ormore processors, cause the device to perform actions as illustrated inthe accompanying drawings and described in the specification. The orderof events or actions, as shown in a flow chart of this disclosure, mayoccur and/or may be performed in any logically coherent order. In someexamples, at least two of the events or actions shown may occur or maybe performed at least in part simultaneously and/or in parallel. In someexamples, one or more additional events or actions may occur or may beperformed prior to, after, or in between the events or actions shown inthe flow charts of the present disclosure.

FIG. 38 shows an example flow diagram in accordance with several ofvarious embodiments of the present disclosure. At 3810, a wirelessdevice may receive: first configuration parameters forlisten-before-talk (LBT) failure recovery; and second configurationparameters, of a scheduling request configuration, comprising ascheduling request identifier associated with consistent LBT failurerecovery. At 3820, the wireless device may trigger, based on the firstconfiguration parameters, consistent LBT failures for one or more firstserving cells. At 3830, the wireless device may transmit a schedulingrequest, via a scheduling request resource: based on the secondconfiguration parameters; in response to no uplink resources, on one ormore second serving cells for which consistent LBT failure is nottriggered, being available for transmission of an LBT failure mediumaccess control (MAC) control element (CE); and wherein at least one ofthe scheduling request resource and the scheduling request configurationmay indicate a third serving cell. At 3840, the wireless device mayreceive an uplink grant for the third serving cell. At 3850, thewireless device may transmit the LBT failure MAC CE based on the uplinkgrant.

In an example embodiment, the first configuration parameters, receivedat 3810, may comprise: a first parameter indicating a first number ofLBT failure instances; and a second parameter indicating a first valueof an LBT failure detection timer. In an example embodiment, thewireless device may increment an LBT counter by one based on an LBTfailure of an LBT procedure for an uplink transmission. In an exampleembodiment, triggering a consistent LBT failure may be based on the LBTcounter reaching the first number. In an example embodiment, thewireless device may start the LBT failure detection timer, with thefirst value, based on the LBT failure.

In an example embodiment, the at least one of the scheduling requestresource and the scheduling request configuration, at 3830, may indicateone or more third serving cells, comprising the third serving cell,without consistent uplink LBT failure.

In an example embodiment, the scheduling request resource via which thescheduling request is transmitted at 3830, may be on the third servingcell; and the third serving cell, for which the uplink grant is receivedat 3840, may be the same cell that the scheduling request istransmitted.

In an example embodiment, the scheduling request resource via which thescheduling request is transmitted at 3830, may be on a cell; and thethird serving cell, for which the uplink grant is received at 3840, maybe based on the cell that the scheduling request is transmitted.

In an example embodiment, the third serving cell, at 3830, may be alicensed cell.

In an example embodiment, the third serving cell, at 3830, may be aprimary cell.

In an example embodiment, the LBT failure MAC CE, at 3850, may comprisea plurality of bits. Each bit, of the plurality of bits, may correspondto a serving cell. A first value of the bit may indicate consistent LBTfailure for the corresponding serving cell.

In an example embodiment, the triggering the consistent LBT failures, at3820, may be for active bandwidth parts of the one or more first servingcells.

In an example embodiment, the LBT failure MAC CE, at 3850, may be of oneoctet or four octets. A logical channel identifier (LCID) associatedwith the LBT failure MAC CE may be: a first LCID if the LBT failure MACCE is of one octet; and a second LCID if the LBT failure MAC CE is offour octets.

FIG. 39 shows an example flow diagram in accordance with several ofvarious embodiments of the present disclosure. At 3910, a base stationmay transmit first configuration parameters for listen-before-talk (LBT)failure recovery; and second configuration parameters, of a schedulingrequest configuration, comprising a scheduling request identifierassociated with consistent LBT failure recovery. At 3920, the basestation may receive a scheduling request, via a scheduling requestresource: based on the second configuration parameters; and in responseto no uplink resources, on one or more second serving cells for whichconsistent LBT failure is not triggered, being available fortransmission of an LBT failure medium access control (MAC) controlelement (CE). At 3930, the base station may determine, based on at leastone of the scheduling request resource and the scheduling requestconfiguration, a third serving cell. At 3940, the base station maytransmit an uplink grant for the third serving cell. At 3950, the basestation may receive the LBT failure MAC CE based on the uplink grant.

In an example embodiment, the determining the third serving cell, at3930, may comprise determining that the third serving cell is withoutconsistent LBT failure.

In an example embodiment, the scheduling request resource, via which thescheduling request is received at 3920, may be on the third servingcell.

In an example embodiment, the scheduling request resource, via which thescheduling request is received at 3920, may be on on a cell. The thirdserving cell, for which the uplink grant is transmitted at 3940, may bebased on the cell that the scheduling request is received at 3920.

In an example embodiment, the third serving cell, at 3930, may be aprimary cell.

In an example embodiment, the third serving cell, at 3930, may be anunlicensed cell.

FIG. 40 shows an example flow diagram in accordance with several ofvarious embodiments of the present disclosure. At 4010, a wirelessdevice may trigger consistent listen-before-talk (LBT) failures for oneor more first serving cells. At 4020, the wireless device may transmit ascheduling request via a resource associated with a scheduling requestconfiguration for LBT failure recovery: in response to no uplinkresources, on one or more second serving cells for which consistent LBTfailure is not triggered, being available for transmission of an LBTfailure medium access control (MAC) control element (CE); and wherein atleast one of the resource and the scheduling request configuration mayindicate a third serving cell. At 4030, the wireless device may receivean uplink grant for the third serving cell. At 4040, the wireless devicemay transmit the LBT failure MAC CE based on the uplink grant.

FIG. 41 shows an example flow diagram in accordance with several ofvarious embodiments of the present disclosure. At 4110, a wirelessdevice may receive: first configuration parameters of a plurality ofcells; and second configuration parameters of a scheduling requestconfiguration. At 4120, the wireless device may transmit a schedulingrequest via a resource associated with the scheduling requestconfiguration, wherein at least one of the resource and the schedulingrequest configuration indicates a cell in the plurality of cells. At4130, the wireless device may receive an uplink grant for the cell. At4140, the wireless device may transmit a transport block based on theuplink grant.

FIG. 42 shows an example flow diagram in accordance with several ofvarious embodiments of the present disclosure. At 4210, a base stationmay transmit: first configuration parameters of a plurality of cells;and second configuration parameters of a scheduling requestconfiguration. At 4220, the base station may receive a schedulingrequest via a resource associated with the scheduling requestconfiguration. At 4230, the base station may determine a cell, of theplurality of cells, based on at least one of the scheduling requestresource and the scheduling request configuration. At 4240, the basestation may transmit an uplink grant for the cell. At 4250, the basestation may receive a transport block based on the uplink grant.

FIG. 43 shows an example flow diagram in accordance with several ofvarious embodiments of the present disclosure. At 4310, a wirelessdevice may trigger consistent listen-before-talk (LBT) failures for oneor more first serving cells. At 4320, the wireless device may determinethat no uplink resources, on one or more second serving cells for whichconsistent LBT failure is not triggered, are available for transmissionof an LBT failure medium access control (MAC) control element (CE). At4330, the wireless device may transmit a scheduling request based on theone or more first serving cells not comprising a primary cell.

FIG. 44 shows an example flow diagram in accordance with several ofvarious embodiments of the present disclosure. At 4410, a wirelessdevice may trigger consistent listen-before-talk (LBT) failure for asecondary cell. At 4420, the wireless device may determine that nouplink resources, on one or more serving cells for which consistent LBTfailure is not triggered, are available for transmission of an LBTfailure medium access control (MAC) control element (CE). At 4430, thewireless device may transmit a scheduling request based on a randomaccess process, for LBT failure recovery, is not ongoing on a primarycell.

In an example embodiment, the random access process, at 4430, may be forLBT failure recovery based on consistent LBT failure on the primarycell.

In an example embodiment, the wireless device may receive configurationparameters of a scheduling request configuration for LBT failurerecovery wherein the transmitting the scheduling request, at 4430, maybe via a scheduling request resource associated with the schedulingrequest configuration.

In an example embodiment, the wireless device may receive an uplinkgrant. The wireless device may transmit the LBT failure MAC CE based onthe uplink grant.

FIG. 45 shows an example flow diagram in accordance with several ofvarious embodiments of the present disclosure. At 4510, a wirelessdevice may trigger consistent listen-before-talk (LBT) failure for oneor more serving cells. At 4520, the wireless device may transmit an LBTfailure medium access control (MAC) control element (CE) comprising aplurality of bits comprising a first bit and a second plurality of bits.The plurality of bits may be associated with a plurality of indexes. Thefirst bit may be associated with a lowest index, in the plurality ofindexes, and may correspond to a primary cell. The second plurality ofbits may correspond to a plurality of secondary cells. A first value ofa bit, in the plurality of bits, may indicate that consistent LBTfailure is triggered for a serving cell corresponding to the bit. Asecond value of the bit may indicate that consistent LBT failure is nottriggered for the serving cell corresponding to the bit.

Various exemplary embodiments of the disclosed technology are presentedas example implementations and/or practices of the disclosed technology.The exemplary embodiments disclosed herein are not intended to limit thescope. Persons of ordinary skill in the art will appreciate that variouschanges can be made to the disclosed embodiments without departure fromthe scope. After studying the exemplary embodiments of the disclosedtechnology, alternative aspects, features and/or embodiments will becomeapparent to one of ordinary skill in the art. Without departing from thescope, various elements or features from the exemplary embodiments maybe combined to create additional embodiments. The exemplary embodimentsare described with reference to the drawings. The figures and theflowcharts that demonstrate the benefits and/or functions of variousaspects of the disclosed technology are presented for illustrationpurposes only. The disclosed technology can be flexibly configuredand/or reconfigured such that one or more elements of the disclosedembodiments may be employed in alternative ways. For example, an elementmay be optionally used in some embodiments or the order of actionslisted in a flowchart may be changed without departure from the scope.

An example embodiment of the disclosed technology may be configured tobe performed when deemed necessary, for example, based on one or moreconditions in a wireless device, a base station, a radio and/or corenetwork configuration, a combination thereof and/or alike. For example,an example embodiment may be performed when the one or more conditionsare met. Example one or more conditions may be one or moreconfigurations of the wireless device and/or base station, traffic loadand/or type, service type, battery power, a combination of thereofand/or alike. In some scenarios and based on the one or more conditions,one or more features of an example embodiment may be implementedselectively.

In this disclosure, the articles “a” and “an” used before a group of oneor more words are to be understood as “at least one” or “one or more” ofwhat the group of the one or more words indicate. The use of the term“may” before a phrase is to be understood as indicating that the phraseis an example of one of a plurality of useful alternatives that may beemployed in an embodiment in this disclosure.

In this disclosure, an element may be described using the terms“comprises”, “includes” or “consists of” in combination with a list ofone or more components. Using the terms “comprises” or “includes”indicates that the one or more components are not an exhaustive list forthe description of the element and do not exclude components other thanthe one or more components. Using the term “consists of” indicates thatthe one or more components is a complete list for description of theelement. In this disclosure, the term “based on” is intended to mean“based at least in part on”. The term “based on” is not intended to mean“based only on”. In this disclosure, the term “and/or” used in a list ofelements indicates any possible combination of the listed elements. Forexample, “X, Y, and/or Z” indicates X; Y; Z; X and Y; X and Z; Y and Z;or X, Y, and Z.

Some elements in this disclosure may be described by using the term“may” in combination with a plurality of features. For brevity and easeof description, this disclosure may not include all possiblepermutations of the plurality of features. By using the term “may” incombination with the plurality of features, it is to be understood thatall permutations of the plurality of features are being disclosed. Forexample, by using the term “may” for description of an element with fourpossible features, the element is being described for all fifteenpermutations of the four possible features. The fifteen permutationsinclude one permutation with all four possible features, fourpermutations with any three features of the four possible features, sixpermutations with any two features of the four possible features andfour permutations with any one feature of the four possible features.

Although mathematically a set may be an empty set, the term set used inthis disclosure is a nonempty set. Set B is a subset of set A if everyelement of set B is in set A. Although mathematically a set has an emptysubset, a subset of a set is to be interpreted as a non-empty subset inthis disclosure. For example, for set A={subcarrier1, subcarrier2}, thesubsets are {subcarrier1}, {subcarrier2} and {subcarrier1, subcarrier2}.

In this disclosure, the phrase “based on” may be used equally with“based at least on” and what follows “based on” or “based at least on”indicates an example of one of plurality of useful alternatives that maybe used in an embodiment in this disclosure. The phrase “in response to”may be used equally with “in response at least to” and what follows “inresponse to” or “in response at least to” indicates an example of one ofplurality of useful alternatives that may be used in an embodiment inthis disclosure. The phrase “depending on” may be used equally with“depending at least on” and what follows “depending on” or “depending atleast on” indicates an example of one of plurality of usefulalternatives that may be used in an embodiment in this disclosure. Thephrases “employing” and “using” and “employing at least” and “using atleast” may be used equally in this in this disclosure and what follows“employing” or “using” or “employing at least” or “using at least”indicates an example of one of plurality of useful alternatives that maybe used in an embodiment in this disclosure.

The example embodiments disclosed in this disclosure may be implementedusing a modular architecture comprising a plurality of modules. A modulemay be defined in terms of one or more functions and may be connected toone or more other elements and/or modules. A module may be implementedin hardware, software, firmware, one or more biological elements (e.g.,an organic computing device and/or a neurocomputer) and/or a combinationthereof and/or alike. Example implementations of a module may be assoftware code configured to be executed by hardware and/or a modelingand simulation program that may be coupled with hardware. In an example,a module may be implemented using general-purpose or special-purposeprocessors, digital signal processors (DSPs), microprocessors,microcontrollers, application-specific integrated circuits (ASICs),programmable logic devices (PLDs) and/or alike. The hardware may beprogrammed using machine language, assembly language, high-levellanguage (e.g., Python, FORTRAN, C, C++ or the like) and/or alike. In anexample, the function of a module may be achieved by using a combinationof the mentioned implementation methods.

What is claimed is:
 1. A method comprising: receiving, by a wirelessdevice, first configuration parameters of a scheduling request (SR)configuration associated with recovery from a listen-before-talk (LBT)event comprising a plurality of LBT failures; triggering the LBT eventfor one or more first cells; in response to no uplink resources, on oneor more second cells for which the LBT event is not triggered, beingavailable for transmission of an LBT failure control element,transmitting a SR via a SR resource based on the first configurationparameters; wherein: the SR indicates a request for uplink resources;and the request excludes resources on the one or more first cells; andtransmitting the LBT failure control element based on an uplink grant.2. The method of claim 1, wherein at least one of the SR resource andthe SR configuration indicates one or more serving cells for which theLBT event is not triggered.
 3. The method of claim 1, wherein a servingcell, of the uplink grant, is based on a cell that the SR istransmitted.
 4. The method of claim 1, wherein a serving cell, of theuplink grant, is the same cell that the SR is transmitted.
 5. The methodof claim 1, wherein a serving cell, of the uplink grant, is a licensedcell.
 6. The method of claim 1, wherein a serving cell, of the uplinkgrant, is a primary cell.
 7. The method of claim 1, further comprising:receiving second configuration parameters, for LBT failure recovery,comprising: a first parameter indicating a first number of LBT failureinstances; and a second parameter indicating a first value of an LBTfailure detection timer; incrementing an LBT counter by one based on anLBT failure of an LBT procedure for an uplink transmission; and startingthe LBT failure detection timer, with the first value, based on the LBTfailure.
 8. The method of claim 7, wherein triggering the LBT event: isbased on the LBT counter reaching the first number; and indicatesconsistent LBT failures.
 9. The method of claim 1, wherein: the LBTfailure control element comprises a plurality of bits; each bit, of theplurality of bits, corresponds to a cell; and a first value of a bit, ofthe plurality of bits, indicates that the LBT event is triggered for thecorresponding cell.
 10. The method of claim 1, wherein: the LBT failurecontrol element is of one octet or four octets; and a logical channelidentifier (LCID) associated with the LBT failure control element is: afirst LCID if the LBT failure control element is of one octet; and asecond LCID if the LBT failure control element is of four octets.
 11. Awireless device comprising: one or more processors; and memory storinginstructions that, when executed by the one or more processors, causethe wireless device to: receive first configuration parameters of ascheduling request (SR) configuration associated with recovery from alisten-before-talk (LBT) event comprising a plurality of LBT failures;trigger the LBT event for one or more first cells; in response to nouplink resources, on one or more second cells for which the LBT event isnot triggered, being available for transmission of an LBT failurecontrol element, transmit a SR via a SR resource based on the firstconfiguration parameters; wherein: the SR indicates a request for uplinkresources; and the request excludes resources on the one or more firstcells; and transmit the LBT failure control element based on an uplinkgrant.
 12. The wireless device of claim 11, wherein at least one of theSR resource and the SR configuration indicates one or more serving cellsfor which the LBT event is not triggered.
 13. The wireless device ofclaim 11, wherein a serving cell, of the uplink grant, is based on acell that the SR is transmitted.
 14. The wireless device of claim 11,wherein a serving cell, of the uplink grant, is the same cell that theSR is transmitted.
 15. The wireless device of claim 11, wherein aserving cell, of the uplink grant, is a licensed cell.
 16. The wirelessdevice of claim 11, wherein a serving cell, of the uplink grant, is aprimary cell.
 17. The wireless device of claim 11, wherein theinstructions, when executed by the one or more processors, further causethe wireless device to: receive second configuration parameters, for LBTfailure recovery, comprising: a first parameter indicating a firstnumber of LBT failure instances; and a second parameter indicating afirst value of an LBT failure detection timer; increment an LBT counterby one based on an LBT failure of an LBT procedure for an uplinktransmission; and start the LBT failure detection timer, with the firstvalue, based on the LBT failure.
 18. The wireless device of claim 17,wherein triggering the LBT event: is based on the LBT counter reachingthe first number; and indicates consistent LBT failures.
 19. Thewireless device of claim 17, wherein: the LBT failure control elementcomprises a plurality of bits; each bit, of the plurality of bits,corresponds to a cell; and a first value of a bit, of the plurality ofbits, indicates that the LBT event is triggered for the correspondingcell.
 20. The wireless device of claim 11, wherein: the LBT failurecontrol element is of one octet or four octets; and a logical channelidentifier (LCID) associated with the LBT failure control element is: afirst LCID if the LBT failure control element is of one octet; and asecond LCID if the LBT failure control element is of four octets.